scsi: ufs: issue request sense before sending Start Stop Unit

Issue request sense before sending START_STOP_UNIT to the device
well-known logical unit (w-lun) to make sure that the device w-lun
unit attention condition is cleared.

Change-Id: I3666b96624ee02278802f624df2ce33c5969d877
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>