Fix hostapd segfault on beacon hint event

Commit 795baf773f6d53bae3cfae4df6edda63e5022344 ('hostapd: Filter
channel list updated events after country code change') uses the
EVENT_CHANNEL_LIST_CHANGED data pointer, but it updated only one of the
callers to provide that data. NL80211_CMD_REG_BEACON_HINT event was
still sending the event without the initiator data and resulted in NULL
pointer dereference, e.g., if a scan was run while hostapd was running
and the driver was in world roaming state and enabled a channel for
active scans.

Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>

src/drivers/driver.h

@@ -47,6 +47,7 @@ enum reg_change_initiator {
 	REGDOM_SET_BY_USER,
 	REGDOM_SET_BY_DRIVER,
 	REGDOM_SET_BY_COUNTRY_IE,
+	REGDOM_BEACON_HINT,
 };
 
 /**

src/drivers/driver_nl80211.c

@@ -3000,8 +3000,10 @@ static void do_process_drv_event(struct i802_bss *bss, int cmd,
 		break;
 	case NL80211_CMD_REG_BEACON_HINT:
 		wpa_printf(MSG_DEBUG, "nl80211: Regulatory beacon hint");
+		os_memset(&data, 0, sizeof(data));
+		data.channel_list_changed.initiator = REGDOM_BEACON_HINT;
 		wpa_supplicant_event(drv->ctx, EVENT_CHANNEL_LIST_CHANGED,
-				     NULL);
+				     &data);
 		break;
 	case NL80211_CMD_NEW_STATION:
 		nl80211_new_station_event(drv, tb);