[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/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 493abf9..937ad32 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1126,7 +1126,7 @@
 	__ipv6_dev_mc_dec(idev, &maddr);
 }
 
-void addrconf_join_anycast(struct inet6_ifaddr *ifp)
+static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
 {
 	struct in6_addr addr;
 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
@@ -1135,7 +1135,7 @@
 	ipv6_dev_ac_inc(ifp->idev->dev, &addr);
 }
 
-void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
+static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
 {
 	struct in6_addr addr;
 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);