mac80211: skip HT parsing if HW does not support HT

This patch will also fix the odd freeze which occurred
when minstrel_ht connects to an 802.11n network with
legacy hardware.

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/mac80211/ht.c

@@ -29,7 +29,7 @@ void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_supported_band *sband,
 
 	memset(ht_cap, 0, sizeof(*ht_cap));
 
-	if (!ht_cap_ie)
+	if (!ht_cap_ie || !sband->ht_cap.ht_supported)
 		return;
 
 	ht_cap->ht_supported = true;