Commit 
8cb34819cdd5d(blk-mq: unshared timeout handler) introduces
blk-mq's own timeout handler, and removes following line:
	blk_queue_rq_timed_out(q, blk_mq_rq_timed_out);
which then causes blk_add_timer() to bypass adding the timer,
since blk-mq no longer has q->rq_timed_out_fn defined.
This patch fixes the problem by bypassing the check for blk-mq,
so that both request deadlines are still set and the rolling
timer updated.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
 
        struct request_queue *q = req->q;
        unsigned long expiry;
 
-       if (!q->rq_timed_out_fn)
+       /* blk-mq has its own handler, so we don't need ->rq_timed_out_fn */
+       if (!q->mq_ops && !q->rq_timed_out_fn)
                return;
 
        BUG_ON(!list_empty(&req->timeout_list));