ath9k: Improve debugfs printout for stations.

Add interface address so it can be mapped to a local
interface.  Add max-ampdu and mpdu-density.

Print out the tid->baw_size

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 4415e89..93b45b4 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -253,6 +253,7 @@
 #ifdef CONFIG_ATH9K_DEBUGFS
 	struct list_head list; /* for sc->nodes */
 	struct ieee80211_sta *sta; /* station struct we're part of */
+	struct ieee80211_vif *vif; /* interface with which we're associated */
 #endif
 	struct ath_atx_tid tid[WME_NUM_TID];
 	struct ath_atx_ac ac[WME_NUM_AC];