ath9k: Update beacon RSSI

ANI uses the beacon RSSI for its operation.
Update this properly.

Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/recv.c

@@ -252,6 +252,10 @@ static int ath_rx_prepare(struct sk_buff *skb, struct ath_desc *ds,
 	else if (ds->ds_rxstat.rs_rssi > 127)
 		ds->ds_rxstat.rs_rssi = 127;
 
+	/* Update Beacon RSSI, this is used by ANI. */
+	if (ieee80211_is_beacon(fc))
+		sc->nodestats.ns_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;
 	rx_status->freq = hw->conf.channel->center_freq;