ath9k: Use ah_curchan and remove sc_curchan which is redundant

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/rc.c b/drivers/net/wireless/ath9k/rc.c
index 20e1084..1392361 100644
--- a/drivers/net/wireless/ath9k/rc.c
+++ b/drivers/net/wireless/ath9k/rc.c
@@ -847,9 +847,9 @@
 	/* For half and quarter rate channles use different
 	 * rate tables
 	 */
-	if (sc->sc_curchan.channelFlags & CHANNEL_HALF)
+	if (sc->sc_ah->ah_curchan->channelFlags & CHANNEL_HALF)
 		ar5416_sethalf_ratetable(asc);
-	else if (sc->sc_curchan.channelFlags & CHANNEL_QUARTER)
+	else if (sc->sc_ah->ah_curchan->channelFlags & CHANNEL_QUARTER)
 		ar5416_setquarter_ratetable(asc);
 	else /* full rate */
 		ar5416_setfull_ratetable(asc);