em_ipset: use dev_net() accessor

Randy found that if network namespace not enabled then
nd_net does not exist and would cause compilation failure.

This is handled correctly by using the dev_net() macro.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sched/em_ipset.c

@@ -24,7 +24,7 @@ static int em_ipset_change(struct tcf_proto *tp, void *data, int data_len,
 {
 	struct xt_set_info *set = data;
 	ip_set_id_t index;
-	struct net *net = qdisc_dev(tp->q)->nd_net;
+	struct net *net = dev_net(qdisc_dev(tp->q));
 
 	if (data_len != sizeof(*set))
 		return -EINVAL;
@@ -46,7 +46,7 @@ static void em_ipset_destroy(struct tcf_proto *p, struct tcf_ematch *em)
 {
 	const struct xt_set_info *set = (const void *) em->data;
 	if (set) {
-		ip_set_nfnl_put(qdisc_dev(p->q)->nd_net, set->index);
+		ip_set_nfnl_put(dev_net(qdisc_dev(p->q)), set->index);
 		kfree((void *) em->data);
 	}
 }