ath9k: Fix RTC reset for AR5416

For AR5416 chipsets, clearing RTC_RESET_EN when setting
the chip to SLEEP mode results in high power consumption.
This patch fixes this issue by not clearing it for AR5416.
Signed-off-by: NSujith <Sujith.Manoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/hw.c

@@ -2851,8 +2851,9 @@ static void ath9k_set_power_sleep(struct ath_hw *ah, int setChip)
 		if (!AR_SREV_9100(ah))
 			REG_WRITE(ah, AR_RC, AR_RC_AHB | AR_RC_HOSTIF);
 
-		REG_CLR_BIT(ah, (AR_RTC_RESET),
-			    AR_RTC_RESET_EN);
+		if(!AR_SREV_5416(ah))
+			REG_CLR_BIT(ah, (AR_RTC_RESET),
+				    AR_RTC_RESET_EN);
 	}
 }