[IPV6]: Introduce inet6_timewait_sock

Out of tcp6_timewait_sock, that now is just an aggregation of
inet_timewait_sock and inet6_timewait_sock, using tw_ipv6_offset in struct
inet_timewait_sock, that is common to the IPv6 transport protocols that use
timewait sockets, like DCCP and TCP.

tw_ipv6_offset plays the struct inet_sock pinfo6 role, i.e. for the generic
code to find the IPv6 area in a timewait sock.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index a60585f..704fb73 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1195,7 +1195,7 @@
 int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2)
 {
 	const struct in6_addr *sk_rcv_saddr6 = &inet6_sk(sk)->rcv_saddr;
-	const struct in6_addr *sk2_rcv_saddr6 = tcp_v6_rcv_saddr(sk2);
+	const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2);
 	u32 sk_rcv_saddr = inet_sk(sk)->rcv_saddr;
 	u32 sk2_rcv_saddr = inet_rcv_saddr(sk2);
 	int sk_ipv6only = ipv6_only_sock(sk);