atheros: move tx/rx chainmask to ath_common

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index 2f00313..54be876 100644
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -62,6 +62,7 @@
 {
 	struct sk_buff *skb = bf->bf_mpdu;
 	struct ath_hw *ah = sc->sc_ah;
+	struct ath_common *common = ath9k_hw_common(ah);
 	struct ath_desc *ds;
 	struct ath9k_11n_rate_series series[4];
 	const struct ath_rate_table *rt;
@@ -109,7 +110,7 @@
 	memset(series, 0, sizeof(struct ath9k_11n_rate_series) * 4);
 	series[0].Tries = 1;
 	series[0].Rate = rate;
-	series[0].ChSel = sc->tx_chainmask;
+	series[0].ChSel = common->tx_chainmask;
 	series[0].RateFlags = (ctsrate) ? ATH9K_RATESERIES_RTS_CTS : 0;
 	ath9k_hw_set11n_ratescenario(ah, ds, ds, 0, ctsrate, ctsduration,
 				     series, 4, 0);