[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/core/utils.c b/net/core/utils.c
index 88eb8b6..7b5970f 100644
--- a/net/core/utils.c
+++ b/net/core/utils.c
@@ -16,7 +16,9 @@
 #include <linux/module.h>
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
+#include <linux/inet.h>
 #include <linux/mm.h>
+#include <linux/net.h>
 #include <linux/string.h>
 #include <linux/types.h>
 #include <linux/random.h>