scsi: ufs: Remove ufshcd_valid_tag()

scsi: ufs: Remove ufshcd_valid_tag()

scsi_add_host() allocates shost->can_queue tags. ufshcd_init() sets
shost->can_queue to hba->nutrs. In other words, we know that tag values
will less than hba->nutrs. Hence remove the checks that verify that
blk_get_request() returns a tag less than hba->nutrs. This check was
introduced by commit 161a1bf21716 ("scsi: ufs: verify command tag
validity").

Keep the tag >= 0 check because it helps to detect use-after-free issues.

Link: https://lore.kernel.org/r/20210722033439.26550-7-bvanassche@acm.org
CC: Avri Altman <avri.altman@wdc.com>
Cc: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>