mwifiex: card reset: enable rescan of non-removable card

mmc_rescan will scan for non-removable cards only once, hence the card
will not be rediscovered.

Signed-off-by: Andreas Fenkart <afenkart@gmail.com>
Acked-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>