igb: correct link test not being run when link is down

The igb online link test was always reporting pass because instead of
checking for if_running it was checking for netif_carrier_ok.

This change corrects the test so that it is run if the interface is running
instead of checking for netif carrier ok.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NEmil Tantilov <emil.s.tantilov@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/igb/igb_ethtool.c

@@ -1823,12 +1823,10 @@ static void igb_diag_test(struct net_device *netdev,
 		dev_info(&adapter->pdev->dev, "online testing starting\n");
 
 		/* PHY is powered down when interface is down */
-		if (!netif_carrier_ok(netdev)) {
-			data[4] = 0;
-		} else {
-			if (igb_link_test(adapter, &data[4]))
+		if (if_running && igb_link_test(adapter, &data[4]))
 			eth_test->flags |= ETH_TEST_FL_FAILED;
-		}
+		else
+			data[4] = 0;
 
 		/* Online tests aren't run; pass by default */
 		data[0] = 0;