[IPV4] fib_rules.c: make struct fib_rules static again

struct fib_rules became global for no good reason.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/fib_rules.c

@@ -100,7 +100,7 @@ static struct fib_rule local_rule = {
 	.r_action =	RTN_UNICAST,
 };
 
-struct hlist_head fib_rules;
+static struct hlist_head fib_rules;
 
 /* writer func called from netlink -- rtnl_sem hold*/