[WLAN]在Softap manager中连接、断开时，添加广播

问题：监听Softap manager中连接、断开时，添加广播，让APP接收到

代码逻辑：

frameworks/opt/net/wifi/service/java/com/android/server/wifi/SoftApManager.java

  public static final String AP_STA_CONNECT_ACTION
            = "test.net.wifi.action.AP_STA_JOIN";
  public static final String AP_STA_DISCONNECT_ACTION
            = "test.net.wifi.action.AP_STA_LEAVE";
  public static final String AP_STA_MAC_ADDR = "ap_sta_mac_addr";
          ...
  private void updateConnectedClients(WifiClient client, boolean isConnected) {
                if (isConnected) {
                    boolean isAllow = checkSoftApClient(mCurrentSoftApConfiguration, client);
                    if (isAllow) {
                        clientList.add(client);
                    } else {
                        return;
                    }
                } else {
                    if (null == clientList.remove(index)) {