MdeModulePkg/SmmS3SaveStateDxe: Change function parameter types

MdeModulePkg/SmmS3SaveStateDxe: Change function parameter types

Change parameter Opcode from UINT16 to UINTN in
BootScriptWrite and BootScriptInsert.
https://bugzilla.tianocore.org/show_bug.cgi?id=1517

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Shenglei Zhang <shenglei.zhang@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>