rt2x00: Use atomic interface iteration in irq context

rt2x00lib_beacondone() is called from interrupt context,
this means we cannot use the mac80211 interface iterator
that uses the rtnl lock (since that uses a mutex which can sleep).
Instead we should use the atomic mac80211 interface iterator.
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rt2x00/rt2x00dev.c

@@ -483,7 +483,7 @@ void rt2x00lib_beacondone(struct rt2x00_dev *rt2x00dev)
 	if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags))
 		return;
 
-	ieee80211_iterate_active_interfaces(rt2x00dev->hw,
+	ieee80211_iterate_active_interfaces_atomic(rt2x00dev->hw,
 						   rt2x00lib_beacondone_iter,
 						   rt2x00dev);