scsi: fnic: Replace sgreset tag with max_tag_id

scsi: fnic: Replace sgreset tag with max_tag_id

sgreset is issued with a SCSI command pointer. The device reset code
assumes that it was issued on a hardware queue, and calls block multiqueue
layer. However, the assumption is broken, and there is no hardware queue
associated with the sgreset, and this leads to a crash due to a null
pointer exception.

Fix the code to use the max_tag_id as a tag which does not overlap with the
other tags issued by mid layer.

Tested by running FC traffic for a few minutes, and by issuing sgreset on
the device in parallel.  Without the fix, the crash is observed right away.
With this fix, no crash is observed.

Reviewed-by: Sesidhar Baddela <sebaddel@cisco.com>
Tested-by: Karan Tilak Kumar <kartilak@cisco.com>
Signed-off-by: Karan Tilak Kumar <kartilak@cisco.com>
Link: https://lore.kernel.org/r/20230817182146.229059-1-kartilak@cisco.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>