net-next: remove useless union keyword

remove useless union keyword in rtable, rt6_info and dn_route.

Since there is only one member in a union, the union keyword isn't useful.

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 7f976af..7f9515c 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -237,7 +237,7 @@
 
 	/* OK, now commit destination to socket.  */
 	sk->sk_gso_type = SKB_GSO_TCPV4;
-	sk_setup_caps(sk, &rt->u.dst);
+	sk_setup_caps(sk, &rt->dst);
 
 	if (!tp->write_seq)
 		tp->write_seq = secure_tcp_sequence_number(inet->inet_saddr,