scsi: ufs: core: Reuse exec_dev_cmd

Move out the actual command issue from exec_dev_cmd it can be used
elsewhere.  While at it, remove a redundant "lrbp->cmd = NULL" assignment.

Also, the device management commands that are originated from the
ufs-bsg code path, are being traced now, which wasn't the case before.

Signed-off-by: Avri Altman <avri.altman@wdc.com>
Link: https://lore.kernel.org/r/20240309081104.5006-3-avri.altman@wdc.com


Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>