MdeModulePkg/HiiDatabase: Add HiiImageEx implementation.

MdeModulePkg/HiiDatabase: Add HiiImageEx implementation.

According to UEFI spec, NewImageEx()/SetImageEx()/DrawImageEx()
implicitly call the non-Ex version interface
of HiiImage protocol.
GetImageEx()/DrawImageIdEx() are the enhanced version of
GetImage()/DrawImageId(), which can support decoding JPEG/PNG
through the help of HiiImageDecoder protocol.

Contributed-under: TianoCore Contribution Agreement 1.0
Reviewed-by: Liming Gao <liming.gao@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Dandan Bi <dandan.bi@intel.com>
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>