ath9k_htc: Set proper firmware offset for Netgear WNDA3200

Netgear WNDA3200 device uses ar7010 firmware but it is failed to set
correct firmware offset on firmware download which causes device initialization
failure.

Cc: stable@kernel.org
Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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

@@ -801,10 +801,16 @@ static int ath9k_hif_usb_download_fw(struct hif_device_usb *hif_dev)
 	}
 	kfree(buf);
 
-	if ((hif_dev->device_id == 0x7010) || (hif_dev->device_id == 0x7015))
+	switch (hif_dev->device_id) {
+	case 0x7010:
+	case 0x7015:
+	case 0x9018:
 		firm_offset = AR7010_FIRMWARE_TEXT;
-	else
+		break;
+	default:
 		firm_offset = AR9271_FIRMWARE_TEXT;
+		break;
+	}
 
 	/*
 	 * Issue FW download complete command to firmware.