scsi: bsg: Fix errno when scsi_bsg_register_queue() fails

scsi: bsg: Fix errno when scsi_bsg_register_queue() fails

When the value of error is printed, it will always be 0. We should print
the correct error code when scsi_bsg_register_queue() fails.

Link: https://lore.kernel.org/r/20211022010201.426746-1-liu.yun@linux.dev
Fixes: ead09dd3aed5 ("scsi: bsg: Simplify device registration")
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>