mmc: sdhci: Add asynchronous interrupt support for sdio cards

SD host controller have asynchronous interrupt support
capability to detect card(sdio) interrupt
even when clocks are gated(to save power).

This patch add support and enable this capability/feature to
of SD host controllers for sdio cards.

Change-Id: Ic1945355a19ebfdb3bd000bf8138d8001cea53f6
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
[subhashj@codeaurora.org: fixed merge conflicts & compilation error]
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
[xiaonian@codeaurora.org: fixed trivial merge conflicts &
compilation error, added caps array to sdhci_setup_host()
function as needed by this patch]
Signed-off-by: Xiaonian Wang <xiaonian@codeaurora.org>