scsi: ufs: clear fields UTRD, UPIU req and rsp before new transfers

scsi: ufs: clear fields UTRD, UPIU req and rsp before new transfers

Some of the data structures (like response UPIU) and/or its elements
(unused fields) should be cleared before sending out the respective
command to UFS device.

This change clears the UPIU response data structure for query commands
and NOP command before sending out the command. We also initialize the
PRDT table length to zero which should take care of commands which
doesn't have any data associated with it. We are also clearing the
unused fields in request UPIU for NOP command.

Reviewed-by: Gilad Broner <gbroner@codeaurora.org>
Reviewed-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>
Tested-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>