MdePkg: Move API and implementation from UefiCpuLib to CpuLib

There are two libraries: MdePkg/CpuLib and UefiCpuPkg/UefiCpuLib. This
patch merges UefiCpuPkg/UefiCpuLib to MdePkg/CpuLib.

Change-Id: Ic26f4c2614ed6bd9840f817d50e47ac1de4bd013
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Zhiguang Liu <zhiguang.liu@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Signed-off-by: Yu Pu <yu.pu@intel.com>
Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn>
Signed-off-by: Zhiguang Liu <zhiguang.liu@intel.com>

UefiCpuPkg/Library/BaseUefiCpuLib/BaseUefiCpuLibNull.c

@@ -0,0 +1,18 @@
+/** @file
+This library contains a dummy function to pass build.
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.
+
+SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+#include <Base.h>
+
+/**
+  Dummy function.
+**/
+VOID
+Dummy (
+  VOID
+  )
+{
+}