StandaloneMmPkg: StandaloneMmIplPei: Guard S3 hob with PcdAcpiS3Enable

The current module checks the value of gEfiAcpiVariableGuid hobs and
could assert if there is no such hob available.

However, these hobs are only available if a platform elects to support
S3. Thus this change moves the hob copy logic behind a PCD check to
prevent unnecessary asserts.

Signed-off-by: Kun Qin <[email protected]>

Author: kuqin12

StandaloneMmPkg/Drivers/StandaloneMmIplPei/MmFoundationHob.c

@@ -1026,9 +1026,12 @@ CreateMmFoundationHobList (
   //
   // Build ACPI variable HOB
   //
-  HobLength = GetRemainingHobSize (*FoundationHobSize, UsedSize);
-  MmIplCopyGuidHob (FoundationHobList + UsedSize, &HobLength, &gEfiAcpiVariableGuid, FALSE);
-  UsedSize += HobLength;
+  if (PcdGetBool (PcdAcpiS3Enable)) {
+    // Only check on this variable when S3 needs it.
+    HobLength = GetRemainingHobSize (*FoundationHobSize, UsedSize);
+    MmIplCopyGuidHob (FoundationHobList + UsedSize, &HobLength, &gEfiAcpiVariableGuid, FALSE);
+    UsedSize += HobLength;
+  }
 
   if (FeaturePcdGet (PcdCpuSmmProfileEnable)) {
     //