cfg80211: don't set privacy w/o key

When wpa_supplicant is used to connect to open networks,
it causes the wdev->wext.keys to point to key memory, but
that key memory is all empty. Only use privacy when there
is a default key to be used.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Tested-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Tested-by: Kalle Valo <kalle.valo@iki.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/wireless/wext-sme.c

@@ -30,6 +30,7 @@ int cfg80211_mgd_wext_connect(struct cfg80211_registered_device *rdev,
 	if (wdev->wext.keys) {
 		wdev->wext.keys->def = wdev->wext.default_key;
 		wdev->wext.keys->defmgmt = wdev->wext.default_mgmt_key;
+		if (wdev->wext.default_key != -1)
 			wdev->wext.connect.privacy = true;
 	}