pkt_sched: Fix locking of qdisc_root with qdisc_root_sleeping_lock()

Use qdisc_root_sleeping_lock() instead of qdisc_root_lock() where
appropriate. The only difference is while dev is deactivated, when
currently we can use a sleeping qdisc with the lock of noop_qdisc.
This shouldn't be dangerous since after deactivation root lock could
be used only by gen_estimator code, but looks wrong anyway.

Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 5cafdd4..8eb79e9 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -205,7 +205,7 @@
 		}
 	}
 
-	root_lock = qdisc_root_lock(q);
+	root_lock = qdisc_root_sleeping_lock(q);
 
 	if (tp == NULL) {
 		/* Proto-tcf does not exist, create new one */