net: sched: sch_qfq: Use non-work-conserving warning handler

A helper function for printing non-work-conserving alarms is added in
commit b00355d ("pkt_sched: sch_hfsc: sch_htb: Add non-work-conserving
 warning handler."). In this commit, use qdisc_warn_nonwc() instead of
WARN_ONCE() to handle the non-work-conserving warning in qfq Qdisc.

Signed-off-by: Liu Jian <liujian56@huawei.com>
Link: https://lore.kernel.org/r/20231023064729.370649-1-liujian56@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net/sched/sch_qfq.c

@@ -1003,7 +1003,7 @@ static inline struct sk_buff *qfq_peek_skb(struct qfq_aggregate *agg,
 	*cl = list_first_entry(&agg->active, struct qfq_class, alist);
 	skb = (*cl)->qdisc->ops->peek((*cl)->qdisc);
 	if (skb == NULL)
-		WARN_ONCE(1, "qfq_dequeue: non-workconserving leaf\n");
+		qdisc_warn_nonwc("qfq_dequeue", (*cl)->qdisc);
 	else
 		*len = qdisc_pkt_len(skb);