MdeModulePkg: Put report status code after event was signaled per PI spec.

MdeModulePkg: Put report status code after event was signaled per PI spec.

For PI spec vol3,
"EFI_SW_DXE_BS_PC_VIRTUAL_ADDRESS_CHANGE_EVENT  The EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event was signaled."
However, in current code base, it is reported before events were signaled.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Elvin Li <elvin.li@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@17123 6f19259b-4bc3-4df7-8a09-765794883524