mac80211: make sta.wme indicate whether QoS is used

Indicating just the peer's capability is fairly pointless
if the local device doesn't support it. Make the variable
track both combined, and remove the 'local support' check
in the TX path.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 94c8c62..201bc68 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1557,7 +1557,8 @@
  * @supp_rates: Bitmap of supported rates (per band)
  * @ht_cap: HT capabilities of this STA; restricted to our own capabilities
  * @vht_cap: VHT capabilities of this STA; restricted to our own capabilities
- * @wme: indicates whether the STA supports QoS/WME.
+ * @wme: indicates whether the STA supports QoS/WME (if local devices does,
+ *	otherwise always false)
  * @drv_priv: data area for driver use, will always be aligned to
  *	sizeof(void *), size is determined in hw information.
  * @uapsd_queues: bitmap of queues configured for uapsd. Only valid