MdeModulePkg: Connect VariablePolicy business logic to VariableServices

https://bugzilla.tianocore.org/show_bug.cgi?id=2522

VariablePolicy is an updated interface to
replace VarLock and VarCheckProtocol.

Add connective code to publish the VariablePolicy protocol
and wire it to either the SMM communication interface
or directly into the VariablePolicyLib business logic.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Bret Barkelew <brbarkel@microsoft.com>
Signed-off-by: Bret Barkelew <brbarkel@microsoft.com>
Reviewed-by: Dandan Bi <dandan.bi@intel.com>
Acked-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn>

MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf

@@ -19,6 +19,7 @@
 #  the authentication service provided in this driver will be broken, and the behavior is undefined.
 #
 # Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
+# Copyright (c) Microsoft Corporation.
 # SPDX-License-Identifier: BSD-2-Clause-Patent
 #
 ##
@@ -78,6 +79,8 @@
   AuthVariableLib
   VarCheckLib
   UefiBootServicesTableLib
+  VariablePolicyLib
+  VariablePolicyHelperLib
 
 [Protocols]
   gEfiSmmFirmwareVolumeBlockProtocolGuid        ## CONSUMES