carl9170: don't load bogus nf of chain 1

According to Atheros, chain 1 is not connected.

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/carl9170/carl9170.h b/drivers/net/wireless/ath/carl9170/carl9170.h
index 9f1d603..d43675a 100644
--- a/drivers/net/wireless/ath/carl9170/carl9170.h
+++ b/drivers/net/wireless/ath/carl9170/carl9170.h
@@ -321,7 +321,7 @@
 
 	/* PHY */
 	struct ieee80211_channel *channel;
-	int noise[6];
+	int noise[4];
 	unsigned int chan_fail;
 	unsigned int total_chan_fail;
 	u8 heavy_clip;