scsi: ufs: remove deprecated enum for hw interrupt

These flags are no longer needed after 2fbd009b in 2013.

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>