rtnl: fix the loop index update error in rtnl_dump_ifinfo()

If the link is filtered out, loop index should also be updated. If not,
loop index will not be correct.

Fixes: dc599f76 ("net: Add support for filtering link dump by master device and kind")
Signed-off-by: NZhang Shengju <zhangshengju@cmss.chinamobile.com>
Acked-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/rtnetlink.c

@@ -1609,7 +1609,7 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 		head = &net->dev_index_head[h];
 		hlist_for_each_entry(dev, head, index_hlist) {
 			if (link_dump_filtered(dev, master_idx, kind_ops))
-				continue;
+				goto cont;
 			if (idx < s_idx)
 				goto cont;
 			err = rtnl_fill_ifinfo(skb, dev, RTM_NEWLINK,