Sync ACPICA with Intel's version 20150408.

Sync ACPICA with Intel's version 20150408.

General changes:

* First part of upstream DragonFly support. acdragonfly.h and
  acdragonflyex.h are now in the upstream repo. Various needed
  patches to hook them in should be in the next Intel release.

* _REV now permanently returns 2 (as in other ACPI implementations).

* Windows 2015 (aka Windows 10) _OSI string added.

* Various printf issue fixes.

iasl(8) specific changes:

* Constant folding enhanced.

* SLIC table support updated according to Microsoft's latest spec. It
  dumps as hex data block now (proprietary data).
  This issue was actually found by our sephe on his Compaq CQ45.

* MSDM table support added (handled as proprietary data, just like SLIC).

* -Pn option implemented for the table compiler (was only implemented
  for the ASL compiler).

* Better data table disassembly comments.

* -df option to force the disassembler to assume the table contains AML.

* Some fixes in the EFI version of the tools.

* Small miscellaneous fixes.

For a more detailed list, please see sys/contrib/dev/acpica/changes.txt.