DynamicTablesPkg: Update X64 FADT XPm1aEvtBlk

Copy the provided configuration data for
PM1 event block.

Cc: Sami Mujawar <Sami.Mujawar@arm.com>
Cc: Pierre Gondois <pierre.gondois@arm.com>
Signed-off-by: Abdul Lateef Attar <AbdulLateef.Attar@amd.com>

DynamicTablesPkg/Library/Acpi/Common/AcpiFadtLib/X64/X64FadtGenerator.c

@@ -244,8 +244,8 @@ FadtArchUpdate (
       ));
   } else {
     CopyMem (
-      &Fadt->XPm1aCntBlk,
-      &XpmBlockInfo->XPm1aCntBlk,
+      &Fadt->XPm1aEvtBlk,
+      &XpmBlockInfo->XPm1aEvtBlk,
       sizeof (EFI_ACPI_6_5_GENERIC_ADDRESS_STRUCTURE)
       );
     CopyMem (