8139too: Add netif_napi_del in the driver

For linux-3.18.0
The driver lacks netif_napi_del in the normal path and error path
to match the call of netif_napi_add in rtl8139_init_one.
This patch fixes this problem.
Signed-off-by: NJia-Ju Bai <baijiaju1990@163.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/realtek/8139too.c

@@ -1110,6 +1110,7 @@ static int rtl8139_init_one(struct pci_dev *pdev,
 	return 0;
 
 err_out:
+	netif_napi_del(&tp->napi);
 	__rtl8139_cleanup_dev (dev);
 	pci_disable_device (pdev);
 	return i;
@@ -1124,6 +1125,7 @@ static void rtl8139_remove_one(struct pci_dev *pdev)
 	assert (dev != NULL);
 
 	cancel_delayed_work_sync(&tp->thread);
+	netif_napi_del(&tp->napi);
 
 	unregister_netdev (dev);