mmc: Porting minor fixes for mmc and sdcard

This is a squash of below minor fixes:
--------------------------------------
98ecf61 mmc: core: Make host->card as NULL when
		card is removed
a927374	mmc: core: Remove unused variable cached_ext_csd
04ac7bd	mmc: core: Ignore CRC errors with CMD13 while
		executing tuning
772de4c	mmc: core: update host->card after getting RCA
		for SD card
35cf592	mmc: core: fix race between mmc_power_off and
		mmc_power_up
0b56648	mmc: host: add support to allow SANITIZE operation.

Change-Id: Ib238929eac1a1befc35adb301b1ca6648e00c4db
Signed-off-by: Veerabhadrarao Badiganti <vbadigan@codeaurora.org>
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Sayali Lokhande <sayalil@codeaurora.org>