[NET]: Fix sparse warnings

Of this type, mostly:

CHECK   net/ipv6/netfilter.c
net/ipv6/netfilter.c:96:12: warning: symbol 'ipv6_netfilter_init' was not declared. Should it be static?
net/ipv6/netfilter.c:101:6: warning: symbol 'ipv6_netfilter_fini' was not declared. Should it be static?

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/tcp.h b/include/net/tcp.h
index d958260..d6bcf13 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -1183,4 +1183,16 @@
 extern int tcp_proc_register(struct tcp_seq_afinfo *afinfo);
 extern void tcp_proc_unregister(struct tcp_seq_afinfo *afinfo);
 
+extern struct request_sock_ops tcp_request_sock_ops;
+
+extern int tcp_v4_destroy_sock(struct sock *sk);
+
+#ifdef CONFIG_PROC_FS
+extern int  tcp4_proc_init(void);
+extern void tcp4_proc_exit(void);
+#endif
+
+extern void tcp_v4_init(struct net_proto_family *ops);
+extern void tcp_init(void);
+
 #endif	/* _TCP_H */