[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/af_unix.h b/include/net/af_unix.h
index b60b384..b5d785a 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -1,5 +1,11 @@
 #ifndef __LINUX_NET_AFUNIX_H
 #define __LINUX_NET_AFUNIX_H
+
+#include <linux/config.h>
+#include <linux/socket.h>
+#include <linux/un.h>
+#include <net/sock.h>
+
 extern void unix_inflight(struct file *fp);
 extern void unix_notinflight(struct file *fp);
 extern void unix_gc(void);
@@ -74,5 +80,14 @@
         wait_queue_head_t       peer_wait;
 };
 #define unix_sk(__sk) ((struct unix_sock *)__sk)
+
+#ifdef CONFIG_SYSCTL
+extern int sysctl_unix_max_dgram_qlen;
+extern void unix_sysctl_register(void);
+extern void unix_sysctl_unregister(void);
+#else
+static inline void unix_sysctl_register(void) {}
+static inline void unix_sysctl_unregister(void) {}
+#endif
 #endif
 #endif