Fix WiFi connection check
Fix WiFi connection check

ThaliWifiInfrastructure did not check the case when WiFi is enabled but
device is not connected to any access point

thaliproject/Thali_CordovaPlugin,thaliproject/Thali_CordovaPlugin,thaliproject/Thali_CordovaPlugin,thaliproject/Thali_CordovaPlugin,thaliproject/Thali_CordovaPlugin