scsi: ufs: just use sizeof() for snprintf()

Not much reason to use ARRAY_SIZE() when we know it's for a C string.

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>