ixgbe: prevent link checks while resetting

It some situations the driver sets __IXGBE_RESETTING and then
__IXGBE_DOWN flags. It is possible a link check may sneak in
between.

This patch adds check for both flags.
The idea is to reduce register reads while the PHY is resetting.

Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c

@@ -5978,7 +5978,8 @@ static void ixgbe_spoof_check(struct ixgbe_adapter *adapter)
 static void ixgbe_watchdog_subtask(struct ixgbe_adapter *adapter)
 {
 	/* if interface is down do nothing */
-	if (test_bit(__IXGBE_DOWN, &adapter->state))
+	if (test_bit(__IXGBE_DOWN, &adapter->state) ||
+	    test_bit(__IXGBE_RESETTING, &adapter->state))
 		return;
 
 	ixgbe_watchdog_update_link(adapter);