mac80211: defines for AC numbers

In many places we've just hardcoded the
AC numbers -- which is a relic from the
original mac80211 (d80211). Add constants
for them so we know what we're talking
about.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 1248369..5b0fff2 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -97,6 +97,20 @@
 };
 
 /**
+ * enum ieee80211_ac_numbers - AC numbers as used in mac80211
+ * @IEEE80211_AC_VO: voice
+ * @IEEE80211_AC_VI: video
+ * @IEEE80211_AC_BE: best effort
+ * @IEEE80211_AC_BK: background
+ */
+enum ieee80211_ac_numbers {
+	IEEE80211_AC_VO		= 0,
+	IEEE80211_AC_VI		= 1,
+	IEEE80211_AC_BE		= 2,
+	IEEE80211_AC_BK		= 3,
+};
+
+/**
  * struct ieee80211_tx_queue_params - transmit queue configuration
  *
  * The information provided in this structure is required for QoS