In PI 1.5 version, system management mode name(SMM) has been changed to Management Mode(MM). It impacts the current code which still use SMM/Smram/SMI keywords. This patch add new definition which use MM/MmRam/MMI keywords to follow new spec definitions. Cc: Michael D Kinney <michael.d.kinney@intel.com> Cc: Liming Gao <liming.gao@intel.com> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Eric Dong <eric.dong@intel.com> Reviewed-by: Liming Gao <liming.gao@intel.com>