ath9k_hw: add AR9271 srev and device ID to allow hw to support ar9271

This allows for hw support to be enabled for ar9271.

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 7bf0f8c..692fd1d 100644
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -609,6 +609,7 @@
 	case AR9285_DEVID_PCIE:
 	case AR5416_DEVID_AR9287_PCI:
 	case AR5416_DEVID_AR9287_PCIE:
+	case AR9271_USB:
 		return true;
 	default:
 		break;
@@ -626,9 +627,8 @@
 	case AR_SREV_VERSION_9280:
 	case AR_SREV_VERSION_9285:
 	case AR_SREV_VERSION_9287:
-		return true;
-	/* Not yet */
 	case AR_SREV_VERSION_9271:
+		return true;
 	default:
 		break;
 	}