correctly set the mode/type for serial channels

lib/serial/GwSerial.h

@@ -43,6 +43,7 @@ class GwSerial : public GwChannelInterface{
         bool getAvailableWrite(){return availableWrite;}
         virtual void begin(unsigned long baud, uint32_t config=SERIAL_8N1, int8_t rxPin=-1, int8_t txPin=-1)=0;
         virtual String getMode() override;
+        virtual int getType() override;
     friend GwSerialStream;
 };
 
@@ -122,6 +123,7 @@ template<typename T>
             setError(serial,logger);
         };
 
+
     };