ath9k: rename ath9k_hw_rfdetach() to ath9k_hw_rf_free()

This makes it clear what this does.

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/hw.c b/drivers/net/wireless/ath/ath9k/hw.c
index 65d2e7d..73dee19 100644
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -1229,7 +1229,7 @@
 	if (!AR_SREV_9100(ah))
 		ath9k_hw_ani_detach(ah);
 
-	ath9k_hw_rfdetach(ah);
+	ath9k_hw_rf_free(ah);
 	ath9k_hw_setpower(ah, ATH9K_PM_FULL_SLEEP);
 	kfree(ah);
 }