Update "apr" package to version 0.9.7. Changes since version 0.9.6:

Update "apr" package to version 0.9.7. Changes since version 0.9.6:
- Fix crash in apr_dir_make_recursive() for relative path
  when the working directory has been deleted.  [Joe Orton]
- Win32: fix apr_proc_mutex_trylock() to handle WAIT_TIMEOUT,
  returning APR_EBUSY.  [Ronen Mizrahi <ronen@tversity.com>]
- Fix apr_file_read() to catch write failures when flushing pending
  writes for a buffered file.  [Joe Orton]
- Fix apr_file_write() infinite loop on write failure for buffered
  files.  [Erik Huelsmann <ehuels gmail.com>]
- Fix error handling where apr_uid_* and apr_gid_* could segfault
  or return APR_SUCCESS in failure cases.  PR 34053.  [Joe Orton,
  Paul Querna]
- Refactor Win32 condition variables code to address bugs 27654, 34336.
  [Henry Jen <henryjen ztune.net>, E Holyat <eholyat yahoo.com>]
- Support APR_SO_SNDBUF and APR_SO_RCVBUF on Windows.  PR 32177.
  [Sim <sgobbi datamanagement.it>, Jeff Trawick]
- Fix detection of rwlocks on Mac OS X. [Aaron Bannert]
- Fix issue with poll() followed by net I/O yielding EAGAIN on
  Mac OS 10.4 (Darwin 8). [Wilfredo Sanchez]

Update based on patches supplied by Ben Collver. Addresses first part
of PR pkg/31817 by Zafer Aydogan.