Add protocol definitions for smm_variable

Adds protocol definition for the SMM Variable service. Protocol
files are based on EDK2 originals from:
https://github.com/tianocore/edk2/commits/master
b4da6c29f1d36031e04212f53277ce0dcba309f1
Structures and defines are required to be align for compatibility
between EDK2 and TS components.

Signed-off-by: Julian Hall <julian.hall@arm.com>
Change-Id: I3a478cdc5d3a849810abf6c699027f65594b4a83
5 files changed