MdeModulePkg/MdeModulePkg.dec,.uni: Add Protocol, PCDs and string tokens

MdeModulePkg/MdeModulePkg.dec,.uni: Add Protocol, PCDs and string tokens

Add definitions and strings for following new PCDs:

  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType
  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType
  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask

Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>