ipv4: Pass flow key down into ip_append_*().

This way rt->rt_dst accesses are unnecessary.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index be5cc8d..853a670 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -297,7 +297,7 @@
 	struct sk_buff *skb;
 
 	sk = icmp_sk(dev_net((*rt)->dst.dev));
-	if (ip_append_data(sk, icmp_glue_bits, icmp_param,
+	if (ip_append_data(sk, fl4, icmp_glue_bits, icmp_param,
 			   icmp_param->data_len+icmp_param->head_len,
 			   icmp_param->head_len,
 			   ipc, rt, MSG_DONTWAIT) < 0) {