Update common authenticated variable (non PK/KEK/DB/DBX) support to comply with latest UEFI spec.

Signed-off by: tye1
Reviewed-by: geekboy15a
Reviewed-by: sfu5
Reviewed-by: gdong1

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13157 6f19259b-4bc3-4df7-8a09-765794883524
6 files changed