Upgrade xz from 5.0.7 to 5.2.2 on the vendor branch

Upgrade xz from 5.0.7 to 5.2.2 on the vendor branch

5.2.2 (2015-09-29)
    * Fixed bugs in QNX-specific code.
    * Omitted the use of pipe2() even if it is available to avoid
      portability issues with some old Linux and glibc combinations.
    * Updated German translation.
    * Added project files to build static and shared liblzma (not the
      whole XZ Utils) with Visual Studio 2013 update 2 or later.
    * Documented that threaded decompression hasn't been implemented
      yet. A 5.2.0 NEWS entry describing multi-threading support had
      incorrectly said "decompression" when it should have said
      "compression".
5.2.1 (2015-02-26)
    * Fixed a compression-ratio regression in fast mode of LZMA1 and
      LZMA2. The bug is present in 5.1.4beta and 5.2.0 releases.
    * Fixed a portability problem in xz that affected at least OpenBSD.
    * Fixed xzdiff to be compatible with FreeBSD's mktemp which differs
      from most other mktemp implementations.
    * Changed CPU core count detection to use cpuset_getaffinity() on
      FreeBSD.
5.2.0 (2014-12-21)
    Since 5.1.4beta:
    * All fixes from 5.0.8
    * liblzma: Fixed lzma_stream_encoder_mt_memusage() when a preset
      was used.
    * xzdiff: If mktemp isn't installed, mkdir will be used as
      a fallback to create a temporary directory. Installing mktemp
      is still recommended.
    * Updated French, German, Italian, Polish, and Vietnamese
      translations.
    Summary of fixes and new features added in the 5.1.x development
    releases:
    * liblzma:
        - Added support for multi-threaded compression. See the
          lzma_mt structure, lzma_stream_encoder_mt(), and
          lzma_stream_encoder_mt_memusage() in <lzma/container.h>,
          lzma_get_progress() in <lzma/base.h>, and lzma_cputhreads()
          in <lzma/hardware.h> for details.
        - Made the uses of lzma_allocator const correct.
        - Added lzma_block_uncomp_encode() to create uncompressed
          .xz Blocks using LZMA2 uncompressed chunks.
        - Added support for LZMA_IGNORE_CHECK.
        - A few speed optimizations were made.
        - Added support for symbol versioning. It is enabled by default
          on GNU/Linux, other GNU-based systems, and FreeBSD.
        - liblzma (not the whole XZ Utils) should now be buildable
          with MSVC 2013 update 2 or later using windows/config.h.
    * xz:
        - Fixed a race condition in the signal handling. It was
          possible that e.g. the first SIGINT didn't make xz exit
          if reading or writing blocked and one had bad luck. The fix
          is non-trivial, so as of writing it is unknown if it will be
          backported to the v5.0 branch.
        - Multi-threaded compression can be enabled with the
          --threads (-T) option.
          [Fixed: This originally said "decompression".]
        - New command line options in xz: --single-stream,
          --block-size=SIZE, --block-list=SIZES,
          --flush-timeout=TIMEOUT, and --ignore-check.
        - xz -lvv now shows the minimum xz version that is required to
          decompress the file. Currently it is 5.0.0 for all supported
          .xz files except files with empty LZMA2 streams require 5.0.2.
    * xzdiff and xzgrep now support .lzo files if lzop is installed.
      The .tzo suffix is also recognized as a shorthand for .tar.lzo.
5.1.4beta (2014-09-14)
    * All fixes from 5.0.6
    * liblzma: Fixed the use of presets in threaded encoder
      initialization.
    * xz --block-list and --block-size can now be used together
      in single-threaded mode. Previously the combination only
      worked in multi-threaded mode.
    * Added support for LZMA_IGNORE_CHECK to liblzma and made it
      available in xz as --ignore-check.
    * liblzma speed optimizations:
        - Initialization of a new LZMA1 or LZMA2 encoder has been
          optimized. (The speed of reinitializing an already-allocated
          encoder isn't affected.) This helps when compressing many
          small buffers with lzma_stream_buffer_encode() and other
          similar situations where an already-allocated encoder state
          isn't reused. This speed-up is visible in xz too if one
          compresses many small files one at a time instead running xz
          once and giving all files as command-line arguments.
        - Buffer comparisons are now much faster when unaligned access
          is allowed (configured with --enable-unaligned-access). This
          speeds up encoding significantly. There is arch-specific code
          for 32-bit and 64-bit x86 (32-bit needs SSE2 for the best
          results and there's no run-time CPU detection for now).
          For other archs there is only generic code which probably
          isn't as optimal as arch-specific solutions could be.
        - A few speed optimizations were made to the SHA-256 code.
          (Note that the builtin SHA-256 code isn't used on all
          operating systems.)
    * liblzma can now be built with MSVC 2013 update 2 or later
      using windows/config.h.
    * Vietnamese translation was added.
5.1.3alpha (2013-10-26)
    * All fixes from 5.0.5
    * liblzma:
        - Fixed a deadlock in the threaded encoder.
        - Made the uses of lzma_allocator const correct.
        - Added lzma_block_uncomp_encode() to create uncompressed
          .xz Blocks using LZMA2 uncompressed chunks.
        - Added support for native threads on Windows and the ability
          to detect the number of CPU cores.
    * xz:
        - Fixed a race condition in the signal handling. It was
          possible that e.g. the first SIGINT didn't make xz exit
          if reading or writing blocked and one had bad luck. The fix
          is non-trivial, so as of writing it is unknown if it will be
          backported to the v5.0 branch.
        - Made the progress indicator work correctly in threaded mode.
        - Threaded encoder now works together with --block-list=SIZES.
        - Added preliminary support for --flush-timeout=TIMEOUT.
          It can be useful for (somewhat) real-time streaming. For
          now the decompression side has to be done with something
          else than the xz tool due to how xz does buffering, but this
          should be fixed.
5.1.2alpha (2012-07-04)
    * All fixes from 5.0.3 and 5.0.4
    * liblzma:
        - Fixed a deadlock and an invalid free() in the threaded encoder.
        - Added support for symbol versioning. It is enabled by default
          on GNU/Linux, other GNU-based systems, and FreeBSD.
        - Use SHA-256 implementation from the operating system if one is
          available in libc, libmd, or libutil. liblzma won't use e.g.
          OpenSSL or libgcrypt to avoid introducing new dependencies.
        - Fixed liblzma.pc for static linking.
        - Fixed a few portability bugs.
    * xz --decompress --single-stream now fixes the input position after
      successful decompression. Now the following works:
          echo foo | xz > foo.xz
          echo bar | xz >> foo.xz
          ( xz -dc --single-stream ; xz -dc --single-stream ) < foo.xz
      Note that it doesn't work if the input is not seekable
      or if there is Stream Padding between the concatenated
      .xz Streams.
    * xz -lvv now shows the minimum xz version that is required to
      decompress the file. Currently it is 5.0.0 for all supported .xz
      files except files with empty LZMA2 streams require 5.0.2.
    * Added an *incomplete* implementation of --block-list=SIZES to xz.
      It only works correctly in single-threaded mode and when
      --block-size isn't used at the same time. --block-list allows
      specifying the sizes of Blocks which can be useful e.g. when
      creating files for random-access reading.
5.1.1alpha (2011-04-12)
    * All fixes from 5.0.2
    * liblzma fixes that will also be included in 5.0.3:
        - A memory leak was fixed.
        - lzma_stream_buffer_encode() no longer creates an empty .xz
          Block if encoding an empty buffer. Such an empty Block with
          LZMA2 data would trigger a bug in 5.0.1 and older (see the
          first bullet point in 5.0.2 notes). When releasing 5.0.2,
          I thought that no encoder creates this kind of files but
          I was wrong.
        - Validate function arguments better in a few functions. Most
          importantly, specifying an unsupported integrity check to
          lzma_stream_buffer_encode() no longer creates a corrupt .xz
          file. Probably no application tries to do that, so this
          shouldn't be a big problem in practice.
        - Document that lzma_block_buffer_encode(),
          lzma_easy_buffer_encode(), lzma_stream_encoder(), and
          lzma_stream_buffer_encode() may return LZMA_UNSUPPORTED_CHECK.
        - The return values of the _memusage() functions are now
          documented better.
    * Support for multithreaded compression was added using the simplest
      method, which splits the input data into blocks and compresses
      them independently. Other methods will be added in the future.
      The current method has room for improvement, e.g. it is possible
      to reduce the memory usage.
    * Added the options --single-stream and --block-size=SIZE to xz.
    * xzdiff and xzgrep now support .lzo files if lzop is installed.
      The .tzo suffix is also recognized as a shorthand for .tar.lzo.
    * Support for short 8.3 filenames under DOS was added to xz. It is
      experimental and may change before it gets into a stable release.
5.0.8 (2014-12-21)
    * Fixed an old bug in xzgrep that affected OpenBSD and probably
      a few other operating systems too.
    * Updated French and German translations.
    * Added support for detecting the amount of RAM on AmigaOS/AROS.
    * Minor build system updates.