net: Make flowi ports AF dependent.

Create two sets of port member accessors, one set prefixed by fl4_*
and the other prefixed by fl6_*

This will let us to create AF optimal flow instances.

It will work because every context in which we access the ports,
we have to be fully aware of which AF the flowi is anyways.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/route.h b/include/net/route.h
index 3d814f8..4c207f9 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -157,8 +157,8 @@
 		.fl4_src = saddr,
 		.fl4_tos = tos,
 		.flowi_proto = proto,
-		.fl_ip_dport = dport,
-		.fl_ip_sport = sport,
+		.fl4_dport = dport,
+		.fl4_sport = sport,
 	};
 	if (sk)
 		security_sk_classify_flow(sk, &fl);
@@ -175,7 +175,7 @@
 		.fl4_src = saddr,
 		.fl4_tos = tos,
 		.flowi_proto = IPPROTO_GRE,
-		.fl_gre_key = gre_key,
+		.fl4_gre_key = gre_key,
 	};
 	return ip_route_output_key(net, &fl);
 }
@@ -228,14 +228,16 @@
 					      __be16 sport, __be16 dport,
 					      struct sock *sk, bool can_sleep)
 {
-	struct flowi fl = { .flowi_oif = oif,
-			    .flowi_mark = sk->sk_mark,
-			    .fl4_dst = dst,
-			    .fl4_src = src,
-			    .fl4_tos = tos,
-			    .flowi_proto = protocol,
-			    .fl_ip_sport = sport,
-			    .fl_ip_dport = dport };
+	struct flowi fl = {
+		.flowi_oif = oif,
+		.flowi_mark = sk->sk_mark,
+		.fl4_dst = dst,
+		.fl4_src = src,
+		.fl4_tos = tos,
+		.flowi_proto = protocol,
+		.fl4_sport = sport,
+		.fl4_dport = dport,
+	};
 	struct net *net = sock_net(sk);
 	struct rtable *rt;
 
@@ -264,15 +266,16 @@
 					       __be16 dport, struct sock *sk)
 {
 	if (sport != orig_sport || dport != orig_dport) {
-		struct flowi fl = { .flowi_oif = rt->rt_oif,
-				    .flowi_mark = rt->rt_mark,
-				    .fl4_dst = rt->rt_key_dst,
-				    .fl4_src = rt->rt_key_src,
-				    .fl4_tos = rt->rt_tos,
-				    .flowi_proto = protocol,
-				    .fl_ip_sport = sport,
-				    .fl_ip_dport = dport };
-
+		struct flowi fl = {
+			.flowi_oif = rt->rt_oif,
+			.flowi_mark = rt->rt_mark,
+			.fl4_dst = rt->rt_key_dst,
+			.fl4_src = rt->rt_key_src,
+			.fl4_tos = rt->rt_tos,
+			.flowi_proto = protocol,
+			.fl4_sport = sport,
+			.fl4_dport = dport
+		};
 		if (inet_sk(sk)->transparent)
 			fl.flowi_flags |= FLOWI_FLAG_ANYSRC;
 		if (protocol == IPPROTO_TCP)