mac80211: stop queues temporarily for flushing

Sometimes queues are flushed in the middle of
operation, which can lead to driver issues.
Stop queues temporarily, while flushing, to
avoid transmitting new packets while they are
being flushed.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/mac80211.h

@@ -93,9 +93,11 @@ struct device;
  * enum ieee80211_max_queues - maximum number of queues
  *
  * @IEEE80211_MAX_QUEUES: Maximum number of regular device queues.
+ * @IEEE80211_MAX_QUEUE_MAP: bitmap with maximum queues set
  */
 enum ieee80211_max_queues {
 	IEEE80211_MAX_QUEUES =		16,
+	IEEE80211_MAX_QUEUE_MAP =	BIT(IEEE80211_MAX_QUEUES) - 1,
 };
 
 #define IEEE80211_INVAL_HW_QUEUE	0xff