inet: Pass flowi to ->queue_xmit().

This allows us to acquire the exact route keying information from the
protocol, however that might be managed.

It handles all of the possibilities, from the simplest case of storing
the key in inet->cork.fl to the more complex setup SCTP has where
individual transports determine the flow.

Signed-off-by: David S. Miller <davem@davemloft.net>

net/l2tp/l2tp_ip.c

@@ -508,7 +508,7 @@ static int l2tp_ip_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *m
 	skb_dst_set(skb, dst_clone(&rt->dst));
 
 	/* Queue the packet to IP for output */
-	rc = ip_queue_xmit(skb);
+	rc = ip_queue_xmit(skb, &inet->cork.fl);
 
 error:
 	/* Update stats */