OvmfPkg: Replace GUEST_TYPE with CC_GUEST_TYPE

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3902

Replace GUEST_TYPE with CC_GUEST_TYPE which is defined in
MdePkg/Include/ConfidentialComputingGuestAttr.h.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Zhiguang Liu <zhiguang.liu@intel.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>

OvmfPkg/Library/BaseMemEncryptSevLib/PeiMemEncryptSevLibInternal.c

@@ -36,7 +36,7 @@ GetSevEsWorkArea (
   //
   // If its not SEV guest then SevEsWorkArea is not valid.
   //
-  if ((WorkArea == NULL) || (WorkArea->Header.GuestType != GUEST_TYPE_AMD_SEV)) {
+  if ((WorkArea == NULL) || (WorkArea->Header.GuestType != CcGuestTypeAmdSev)) {
     return NULL;
   }