ath9k_hw: rename ath9k_hw_rf_free() to ath9k_hw_rf_free_ext_banks()

This clarifies this is only required for external radios.

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/phy.h b/drivers/net/wireless/ath/ath9k/phy.h
index 0bbbfbc..477b606 100644
--- a/drivers/net/wireless/ath/ath9k/phy.h
+++ b/drivers/net/wireless/ath/ath9k/phy.h
@@ -29,6 +29,8 @@
 			  u16 modesIndex);
 void ath9k_hw_decrease_chain_power(struct ath_hw *ah,
 				   struct ath9k_channel *chan);
+
+void ath9k_hw_rf_free_ext_banks(struct ath_hw *ah);
 int ath9k_hw_rf_alloc_ext_banks(struct ath_hw *ah);
 
 #define AR_PHY_BASE     0x9800