r8152: don't execute runtime suspend if the tx is not empty

BugLink: http://bugs.launchpad.net/bugs/1662507

[ Upstream commit 6a0b76c0 ]

Runtime suspend shouldn't be executed if the tx queue is not empty,
because the device is not idle.
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

drivers/net/usb/r8152.c

@@ -3515,6 +3515,8 @@ static bool delay_autosuspend(struct r8152 *tp)
 	 */
 	if (!sw_linking && tp->rtl_ops.in_nway(tp))
 		return true;
+	else if (!skb_queue_empty(&tp->tx_queue))
+		return true;
 	else
 		return false;
 }