mmc: sdhci-msm: add nonhotplug support

With some devices like QRD SKUK, SD card could not support
hotplug as there is no cd-gpio, and also could not use polling
way due to power comsumption. So add nonhotplug to meet such
requirement and when SD card lost or removed manually, device
will not crash until next reboot process to detect SD card.

Change-Id: I318d3db72fc09248c5dada2fb6d69ade1bbf85cb
Signed-off-by: Guoping Yu <guopingy@codeaurora.org>