mmc: sdhci-msm: Reset host->pwr and POWER_CONTROL register

When the SD card is removed regulators are never turned ON.
Reset host->pwr and POWER_CONTROL register accordingly.

Change-Id: I6fb9d357c54d172fb3447e4f0b7ceaaf48c9dbf7
Signed-off-by: Sarthak Garg <sartgarg@codeaurora.org>
Signed-off-by: Ram Prakash Gupta <rampraka@codeaurora.org>