SEC checks in IsSevGuest if the PCD defined WorkAreaHeader size matches the size of the WorkAreaHeader struct definition. Set a default value for the PCD to avoid unnecessary DSC/FDF file changes in all OVMF DSC/FDF files. Signed-off-by: Corvin Köhne <c.koehne@beckhoff.com> Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>