rtnetlink: do not set notification for tx_queue_len in do_setlink

NETDEV_CHANGE_TX_QUEUE_LEN event process in rtnetlink_event would
send a notification for userspace and tx_queue_len's setting in
do_setlink would trigger NETDEV_CHANGE_TX_QUEUE_LEN.

So it shouldn't set DO_SETLINK_NOTIFY status for this change to
send a notification any more.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/rtnetlink.c

@@ -2093,7 +2093,7 @@ static int do_setlink(const struct sk_buff *skb,
 				dev->tx_queue_len = orig_len;
 				goto errout;
 			}
-			status |= DO_SETLINK_NOTIFY;
+			status |= DO_SETLINK_MODIFIED;
 		}
 	}