net_sched: sch_mqprio: dont leak kernel memory

mqprio_dump() should make sure all fields of struct tc_mqprio_qopt are
initialized.

Signed-off-by: Eric Dumazet <[e-mail]>
CC: John Fastabend <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/sched/sch_mqprio.c

···
 	struct net_device *dev = qdisc_dev(sch);
 	struct mqprio_sched *priv = qdisc_priv(sch);
 	unsigned char *b = skb_tail_pointer(skb);
-	struct tc_mqprio_qopt opt;
+	struct tc_mqprio_qopt opt = { 0 };
 	struct Qdisc *qdisc;
 	unsigned int i;