CoffeelakeSiliconPkg/Cpu: Add library instances

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=2082



Adds CPU library class instances.

* BaseCpuMailboxLibNull - Generic CPU mailbox interaction services.
* PeiCpuPolicyLib - CPU policy configuration services.
* PeiCpuPolicyLibPreMem - CPU policy pre-memory configuration services.
* PeiDxeSmmCpuPlatformLib - CPU platform services.

Cc: Sai Chaganty <rangasai.v.chaganty@intel.com>
Cc: Chasel Chiu <chasel.chiu@intel.com>
Cc: Nate DeSimone <nathaniel.l.desimone@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Ankit Sinha <ankit.sinha@intel.com>
Signed-off-by: Michael Kubacki <michael.a.kubacki@intel.com>
Reviewed-by: Chasel Chiu <chasel.chiu@intel.com>
Reviewed-by: Nate DeSimone <nathaniel.l.desimone@intel.com>
Reviewed-by: Ankit Sinha <ankit.sinha@intel.com>