ath9k: Remove redundant chainmask check

We get the valid chainmasks on HW attach, checking
it again during reset is redundant. This patch removes the check.
Signed-off-by: NSujith <Sujith.Manoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath9k/hw.c

@@ -2189,14 +2189,6 @@ int ath9k_hw_reset(struct ath_hw *ah, struct ath9k_channel *chan,
 	ah->txchainmask = sc->tx_chainmask;
 	ah->rxchainmask = sc->rx_chainmask;
 
-	if (AR_SREV_9285(ah)) {
-		ah->txchainmask &= 0x1;
-		ah->rxchainmask &= 0x1;
-	} else if (AR_SREV_9280(ah)) {
-		ah->txchainmask &= 0x3;
-		ah->rxchainmask &= 0x3;
-	}
-
 	if (!ath9k_hw_setpower(ah, ATH9K_PM_AWAKE))
 		return -EIO;