MdeModulePkg/SdMmc: update TPL to notify to fix UEFI SCT hang

We have to upgrade the TPL level used by SdMmc stack because the
following flow:

DiskIo2ReadWriteDisk() in logical partition -> PartitionReadBlocksEx()
in logical partition at TPL callback level -> ProbeMediaStatusEx()
with sync request -> DiskIo2ReadWriteDisk() in physical partition ->
 waiting for async task completion.

if the low layer driver doesn't run at TPL_NOTIFY level, it will have
no time to trigger async task and cause system hang.

Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Feng Tian <feng.tian@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>

MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHci.c

@@ -1315,7 +1315,7 @@ SdMmcCreateTrb (
   }
 
   if (Event != NULL) {
-    OldTpl = gBS->RaiseTPL (TPL_CALLBACK);
+    OldTpl = gBS->RaiseTPL (TPL_NOTIFY);
     InsertTailList (&Private->Queue, &Trb->TrbList);
     gBS->RestoreTPL (OldTpl);
   }