pkt_sched: fq: clear time_next_packet for reused flows

When a socket is freed/reallocated, we need to clear time_next_packet
or else we can inherit a prior value and delay first packets of the
new flow.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/sched/sch_fq.c

@@ -255,6 +255,7 @@ static struct fq_flow *fq_classify(struct sk_buff *skb, struct fq_sched_data *q)
 				     f->socket_hash != sk->sk_hash)) {
 				f->credit = q->initial_quantum;
 				f->socket_hash = sk->sk_hash;
+				f->time_next_packet = 0ULL;
 			}
 			return f;
 		}