qlcnic: Stop traffic before performing loopback test

Before conducting loopback test by sending packets, driver should stop transmit
queue and turn off carrier.
Signed-off-by: NJitendra Kalsaria <jitendra.kalsaria@qlogic.com>
Signed-off-by: NShahed Shaikh <shahed.shaikh@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_hw.c

@@ -1500,6 +1500,12 @@ int qlcnic_83xx_loopback_test(struct net_device *netdev, u8 mode)
 		}
 	} while ((adapter->ahw->linkup && ahw->has_link_events) != 1);
 
+	/* Make sure carrier is off and queue is stopped during loopback */
+	if (netif_running(netdev)) {
+		netif_carrier_off(netdev);
+		netif_stop_queue(netdev);
+	}
+
 	ret = qlcnic_do_lb_test(adapter, mode);
 
 	qlcnic_83xx_clear_lb_mode(adapter, mode);