MdePkg: Clarification to the return status of EFI_PEIM_NOTIFY_ENTRY_POINT

MdePkg: Clarification to the return status of EFI_PEIM_NOTIFY_ENTRY_POINT

In Previous PI spec (< PI1.4a) Volume 1, Section 7.4.1, the callback
EFI_PEIM_NOTIFY_ENTRY_POINT is defined. A description for the arguments
are provided but not for the EFI_STATUS return value.

PI1.4a updated EFI_PEIM_NOTIFY_ENTRY_POINT definition to include a new
paragraph with this sentence after the arguments:

"The status code returned from this function is ignored"

This patch is to follow PI1.4a spec to update the code.

Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>