mac80211: set only VO as a U-APSD enabled AC

Some APs experience problems when working with U-APSD. Decrease the
probability of that happening by using legacy mode for all ACs but VO.

The AP that caused us troubles was a Cisco 4410N. It ignores our
setting, and always treats non-VO ACs as legacy.

Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/ieee80211_i.h

@@ -55,11 +55,14 @@ struct ieee80211_local;
 #define TU_TO_JIFFIES(x)	(usecs_to_jiffies((x) * 1024))
 #define TU_TO_EXP_TIME(x)	(jiffies + TU_TO_JIFFIES(x))
 
+/*
+ * Some APs experience problems when working with U-APSD. Decrease the
+ * probability of that happening by using legacy mode for all ACs but VO.
+ * The AP that caused us trouble was a Cisco 4410N. It ignores our
+ * setting, and always treats non-VO ACs as legacy.
+ */
 #define IEEE80211_DEFAULT_UAPSD_QUEUES \
-	(IEEE80211_WMM_IE_STA_QOSINFO_AC_BK |	\
-	 IEEE80211_WMM_IE_STA_QOSINFO_AC_BE |	\
-	 IEEE80211_WMM_IE_STA_QOSINFO_AC_VI |	\
-	 IEEE80211_WMM_IE_STA_QOSINFO_AC_VO)
+	IEEE80211_WMM_IE_STA_QOSINFO_AC_VO
 
 #define IEEE80211_DEFAULT_MAX_SP_LEN		\
 	IEEE80211_WMM_IE_STA_QOSINFO_SP_ALL