SecurityPkg: Tcg2Smm: Remove Unused Functionality

Remove unused MemoryClear SMI Handler, which is no longer
used due to _DSM Memory Clear no longer being used.

SecurityPkg/Tcg/Tcg2Smm/Tcg2Smm.c

@@ -158,6 +158,8 @@ PhysicalPresenceCallback (
   return EFI_SUCCESS;
 }
 
+#if 0 // MU_CHANGE Begin - MemoryClear SMI handler not used
+
 /**
   Software SMI callback for MemoryClear which is called from ACPI method.
 
@@ -233,6 +235,8 @@ MemoryClearCallback (
   return EFI_SUCCESS;
 }
 
+#endif // MU_CHANGE Begin - MemoryClear SMI handler not used
+
 /**
   Notification for SMM ReadyToLock protocol.
 
@@ -325,6 +329,7 @@ InitializeTcgCommon (
 
   mPpSoftwareSmi = SwContext.SwSmiInputValue;
 
+ #if 0  // MU_CHANGE Begin - MemoryClear SMI handler is not used
   SwContext.SwSmiInputValue = (UINTN)-1;
   Status                    = SwDispatch->Register (SwDispatch, MemoryClearCallback, &SwContext, &McSwHandle);
   ASSERT_EFI_ERROR (Status);
@@ -334,6 +339,7 @@ InitializeTcgCommon (
   }
 
   mMcSoftwareSmi = SwContext.SwSmiInputValue;
+ #endif // MU_CHANGE End
 
   //
   // Locate SmmVariableProtocol.