After commit eeb84aa0 ("net_sched: sch_fq: do not assume EDT
packets are ordered"), all skbs get a non zero time_to_send
in flow_queue_add()

This means @time_next_packet variable in fq_dequeue()
can no longer be zero.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>