netfilter: ctnetlink: fix up for "netfilter: conntrack: remove unconfirmed list"

After merging the net-next tree, today's linux-next build (powerpc
ppc64_defconfig) produced this warning:

nf_conntrack_netlink.c:1717 warning: 'ctnetlink_dump_one_entry' defined but not used

Fixes: 8a75a2c1 ("netfilter: conntrack: remove unconfirmed list")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Florian Westphal <fw@strlen.de>

net/netfilter/nf_conntrack_netlink.c

@@ -1714,6 +1714,7 @@ static int ctnetlink_done_list(struct netlink_callback *cb)
 	return 0;
 }
 
+#ifdef CONFIG_NF_CONNTRACK_EVENTS
 static int ctnetlink_dump_one_entry(struct sk_buff *skb,
 				    struct netlink_callback *cb,
 				    struct nf_conn *ct,
@@ -1754,6 +1755,7 @@ static int ctnetlink_dump_one_entry(struct sk_buff *skb,
 
 	return res;
 }
+#endif
 
 static int
 ctnetlink_dump_unconfirmed(struct sk_buff *skb, struct netlink_callback *cb)