ipv4: Export rtm_ipv4_policy.

The MPLS code now needs it.

Fixes: 397fc9e5 ("mpls: route get support")
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/fib_frontend.c

@@ -626,6 +626,7 @@ const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = {
 	[RTA_UID]		= { .type = NLA_U32 },
 	[RTA_MARK]		= { .type = NLA_U32 },
 };
+EXPORT_SYMBOL_GPL(rtm_ipv4_policy);
 
 static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
 			     struct nlmsghdr *nlh, struct fib_config *cfg,