pkt_sched: Fix qstats.qlen updating in dump_stats

Some classful qdiscs miss qstats.qlen updating with q.qlen of their
child qdiscs in dump_stats methods.

Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_mq.c b/net/sched/sch_mq.c
index 600c501..d1dea3d 100644
--- a/net/sched/sch_mq.c
+++ b/net/sched/sch_mq.c
@@ -193,6 +193,7 @@
 	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
 
 	sch = dev_queue->qdisc_sleeping;
+	sch->qstats.qlen = sch->q.qlen;
 	if (gnet_stats_copy_basic(d, &sch->bstats) < 0 ||
 	    gnet_stats_copy_queue(d, &sch->qstats) < 0)
 		return -1;