scsi: ufs: Clear UAC for FFU and RPMB LUNs

In order to conduct FFU or RPMB operations, UFS needs to clear UNIT
ATTENTION condition. Clear it explicitly so that we get no failures during
initialization.

Link: https://lore.kernel.org/r/20201117165839.1643377-4-jaegeuk@kernel.org


Signed-off-by: Jaegeuk Kim <jaegeuk@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>