UefiCpuPkg: Use CpuPageTableLib to convert SMM paging attribute.

Simplify the ConvertMemoryPageAttributes API to convert paging
attribute by CpuPageTableLib. In the new API, it calls
PageTableMap() to update the page attributes of a memory range.
With the PageTableMap() API in CpuPageTableLib, we can remove
the complicated page table manipulating code.

Signed-off-by: Dun Tan <dun.tan@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>

UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/PageTbl.c

@@ -1,7 +1,7 @@
 /** @file
 Page table manipulation functions for IA-32 processors
 
-Copyright (c) 2009 - 2019, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2009 - 2023, Intel Corporation. All rights reserved.<BR>
 Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
 
 SPDX-License-Identifier: BSD-2-Clause-Patent
@@ -31,6 +31,7 @@ SmmInitPageTable (
   InitializeSpinLock (mPFLock);
 
   mPhysicalAddressBits = 32;
+  mPagingMode          = PagingPae;
 
   if (FeaturePcdGet (PcdCpuSmmProfileEnable) ||
       HEAP_GUARD_NONSTOP_MODE ||