ath9k: Use a single opmode variable

ah_opmode and sc_opmode are redundant.
This patch removes sc_opmode.

Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath9k/main.c b/drivers/net/wireless/ath9k/main.c
index 262fd7a..7504b64 100644
--- a/drivers/net/wireless/ath9k/main.c
+++ b/drivers/net/wireless/ath9k/main.c
@@ -472,7 +472,8 @@
 	ath_rate_newstate(sc, avp);
 
 	/* Reclaim beacon resources */
-	if (sc->sc_opmode == ATH9K_M_HOSTAP || sc->sc_opmode == ATH9K_M_IBSS) {
+	if (sc->sc_ah->ah_opmode == ATH9K_M_HOSTAP ||
+	    sc->sc_ah->ah_opmode == ATH9K_M_IBSS) {
 		ath9k_hw_stoptxdma(sc->sc_ah, sc->sc_bhalq);
 		ath_beacon_return(sc, avp);
 	}