scsi: ufs: bsg: Set bsg_queue to NULL after removal

Currently, this does not cause any issues, but I believe it is necessary to
set bsg_queue to NULL after removing it to prevent potential use-after-free
(UAF) access.

Signed-off-by: Guixin Liu <kanie@linux.alibaba.com>
Link: https://lore.kernel.org/r/20241218014214.64533-3-kanie@linux.alibaba.com


Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>