AP: Make sure ieee80211n_allowed_ht40_channel_pair() gets called

We need to call this function after having completed the neighboring
channel scan to figure out whether HT40 can be used and if so, which
channel is the secondary channel.

src/ap/hw_features.c

@@ -424,6 +424,7 @@ static void ieee80211n_check_scan(struct hostapd_iface *iface)
 {
 	struct wpa_scan_results *scan_res;
 	int oper40;
+	int res;
 
 	/* Check list of neighboring BSSes (from scan) to see whether 40 MHz is
 	 * allowed per IEEE 802.11n/D7.0, 11.14.3.2 */
@@ -452,7 +453,8 @@ static void ieee80211n_check_scan(struct hostapd_iface *iface)
 		iface->conf->ht_capab &= ~HT_CAP_INFO_SUPP_CHANNEL_WIDTH_SET;
 	}
 
-	hostapd_setup_interface_complete(iface, 0);
+	res = ieee80211n_allowed_ht40_channel_pair(iface);
+	hostapd_setup_interface_complete(iface, !res);
 }