ath9k: Nuke struct ath9k_node_stats

Other than ns_avgbrssi (Average beacon rssi) no data of
ath9k_node_stats is being used anywhere. Nuke this structure
and move its only useful member to ar5416Anistate. Also cleanup
this redundant data in ath_softc.

Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c
index 61dbdd2..7b62c22 100644
--- a/drivers/net/wireless/ath/ath9k/recv.c
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -222,7 +222,7 @@
 
 	/* Update Beacon RSSI, this is used by ANI. */
 	if (ieee80211_is_beacon(fc))
-		sc->nodestats.ns_avgbrssi = ds->ds_rxstat.rs_rssi;
+		sc->sc_ah->stats.avgbrssi = ds->ds_rxstat.rs_rssi;
 
 	rx_status->mactime = ath_extend_tsf(sc, ds->ds_rxstat.rs_tstamp);
 	rx_status->band = hw->conf.channel->band;