UefiCpuPkg/MpInitLib:remove optional in declaration

To keep the declaration same with definition, remove the last optional
in declaration of WakeUpAP.

Cc: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Signed-off-by: Wenyi Xie <xiewenyi2@huawei.com>

UefiCpuPkg/Library/MpInitLib/MpLib.h

@@ -477,7 +477,7 @@ WakeUpAP (
   IN UINTN             ProcessorNumber,
   IN EFI_AP_PROCEDURE  Procedure               OPTIONAL,
   IN VOID              *ProcedureArgument      OPTIONAL,
-  IN BOOLEAN           WakeUpDisabledAps       OPTIONAL
+  IN BOOLEAN           WakeUpDisabledAps
   );
 
 /**