First round of PI enabling work:

1) PiPeiCis changes (CONST, EFI_PEI_FILE_HANDLE.. etc)
2) Make use of FirmwareVolume 2 protocol.
3) Verified for LakeportX64Pkg (S3) and Nt32Pkg

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@3769 6f19259b-4bc3-4df7-8a09-765794883524

IntelFrameworkModulePkg/Universal/VariablePei/Variable.c

@@ -76,7 +76,7 @@ Returns:
   //
   // Publish the variable capability to other modules
   //
-  return (**PeiServices).InstallPpi (PeiServices, &mPpiListVariable[0]);
+  return (**PeiServices).InstallPpi ((CONST EFI_PEI_SERVICES **) PeiServices, &mPpiListVariable[0]);
 
 }