iwlwifi: cancel scan when down the device

Always cancel scan when stooping device and scan is currently pending,
we should newer have scan running after down device.

To assure we start scan cancel from restart work we have to schedule
abort_scan to different workqueue than priv->workqueue.

Patch fix not cancel scanning when restarting firmware, what is
one of the causes of wdev_cleanup_work warning (together with permanent
network connection lost) reported at
https://bugzilla.redhat.com/show_bug.cgi?id=593566

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Wey-Yi W Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index 36df9a7..d2315de 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -2892,8 +2892,9 @@
 
 	IWL_DEBUG_INFO(priv, DRV_NAME " is going down\n");
 
-	if (!exit_pending)
-		set_bit(STATUS_EXIT_PENDING, &priv->status);
+	iwl_scan_cancel_timeout(priv, 200);
+
+	exit_pending = test_and_set_bit(STATUS_EXIT_PENDING, &priv->status);
 
 	/* Stop TX queues watchdog. We need to have STATUS_EXIT_PENDING bit set
 	 * to prevent rearm timer */
@@ -3503,15 +3504,6 @@
 
 	priv->is_open = 0;
 
-	if (iwl_is_ready_rf(priv) || test_bit(STATUS_SCAN_HW, &priv->status)) {
-		/* stop mac, cancel any scan request and clear
-		 * RXON_FILTER_ASSOC_MSK BIT
-		 */
-		mutex_lock(&priv->mutex);
-		iwl_scan_cancel_timeout(priv, 100);
-		mutex_unlock(&priv->mutex);
-	}
-
 	iwl_down(priv);
 
 	flush_workqueue(priv->workqueue);