fix broken sysinfo (#2381)

Co-authored-by: CaCO3 <caco@ruinelli.ch>

code/components/jomjol_wlan/connect_wlan.h

@@ -9,6 +9,8 @@ int wifi_init_sta(void);
 std::string* getIPAddress();
 std::string* getSSID();
 int get_WIFI_RSSI();
+std::string* getHostname();
+
 bool getWIFIisConnected();
 void WIFIDestroy();