Add ACPI5.1 header file.

Contributed-under: TianoCore Contribution Agreement 1.0

Signed off by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed by: Star Zeng <star.zeng@intel.com>
Reviewed by: Liming Gao <liming.gao@intel.com>





git-svn-id: svn://svn.code.sf.net/p/edk2/code/trunk/edk2/MdePkg@15689 6f19259b-4bc3-4df7-8a09-765794883524