MdeModulePkg/Sd: update the sd detection logic

MdeModulePkg/Sd: update the sd detection logic

If there is no card presented before power on, there would
have no card change interrupt generated. This is a corner
case which can't be handled by old logic.

The patch is used to move card present detection in the front
of card change interrupt detection.

Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Feng Tian <feng.tian@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>