Original use the File Header Machine Field to identify EFI_IMAGE_OPTIONAL_HEADER32 or EFI_IMAGE_OPTIONAL_HEADER64, it cannot correctly handle EBC arch PE32 image. Cc: Liming Gao <liming.gao@intel.com> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Yonghong Zhu <yonghong.zhu@intel.com> Reviewed-by: Liming Gao <liming.gao@intel.com>