[RTNETLINK]: Fix use of wrong skb in do_getlink()

skb is the netlink query, nskb is the reply message.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/rtnetlink.c

@@ -602,7 +602,7 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
 		goto errout;
 	}
 
-	err = rtnl_unicast(skb, NETLINK_CB(skb).pid);
+	err = rtnl_unicast(nskb, NETLINK_CB(skb).pid);
 errout:
 	kfree(iw_buf);
 	dev_put(dev);