misc: rtsx: Fix power down flow

Fix and sort out rtsx driver power down flow

Signed-off-by: Ricky Wu <ricky_wu@realtek.com>
Link: https://lore.kernel.org/r/20200907100718.7672-1-ricky_wu@realtek.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>