scsi: ufs: core: Optimize the hot path

scsi: ufs: core: Optimize the hot path

Set .cmd_size in the SCSI host template such that the SCSI core makes
struct scsi_cmnd and struct ufshcd_lrb adjacent. Convert the cmd->lrbp
and lrbp->cmd memory loads into pointer offset calculations. Remove the
data structure members that became superfluous, namely ufshcd_lrb.cmd
and ufs_hba.lrb. Since ufshcd_lrb.cmd is removed, this pointer cannot be
used anymore to test whether or not a command is a SCSI command.
Introduce a new function for this purpose, namely ufshcd_is_scsi_cmd().

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20251031204029.2883185-24-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>