OvmfPkg/PlatformPei: Refactor MiscInitialization for CloudHV

OvmfPkg/PlatformPei: Refactor MiscInitialization for CloudHV

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3863

Refactor MiscInitialization for CloudHV to set PCD as other platforms
do. Because in the following patch we will split the functions which
set PCDs into two, one for PlatformInitLib, one for PlatformPei.

Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Sebastien Boeuf <sebastien.boeuf@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>