mmc: core: Enable card detect IRQ wake if host needs it

After aquire card detect IRQ, try to enable the IRQ wake if it is valid and
host is capable of MMC_CAP_CD_WAKE.

Change-Id: I6195f38fb6cc9eb1fc22fe9d9fcbff966f6d3650
Signed-off-by: Can Guo <cang@codeaurora.org>