Because terminal doesn't support shift and toggle key state,
ReadKeyStrokeEx just sets the two states to 0.
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
(cherry picked from commit 66f2329446
)