The caller of queue_cmd_ring grabs and releases the lock, so the
tcmu_setup_cmd_timer failure handling inside queue_cmd_ring should not call
mutex_unlock.
Signed-off-by: Mike Christie <mchristi@redhat.com> Reviewed-by: Xiubo Li <xiubli@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>