initialize pointer

Author: myuj

src/esp8266-google-home-notifier.h

@@ -43,7 +43,7 @@ typedef class GoogleHomeNotifier {
   char m_clientid[40] = {0};
 
   TTS tts;
-  WiFiClientSecure* m_client;
+  WiFiClientSecure* m_client = nullptr;
   IPAddress m_ipaddress;
   uint16_t m_port = 0;
   char m_locale[10] = "en";