fixed platform-independent serial ports definitions

Author: ppescher

sam/1.0.3/variants/geolink_opentracker/variant.h

@@ -283,11 +283,10 @@ extern USARTClass Serial3;
 //
 // SERIAL_PORT_HARDWARE_OPEN  Hardware serial ports which are open for use.  Their RX & TX
 //                            pins are NOT connected to anything by default.
-#define SERIAL_PORT_MONITOR         Serial
+#define SERIAL_PORT_MONITOR         SerialUSB
 #define SERIAL_PORT_USBVIRTUAL      SerialUSB
-#define SERIAL_PORT_HARDWARE_OPEN   Serial1
-#define SERIAL_PORT_HARDWARE_OPEN1  Serial2
-#define SERIAL_PORT_HARDWARE_OPEN2  Serial3
+#define SERIAL_PORT_HARDWARE_OPEN   Serial
+#define SERIAL_PORT_HARDWARE_OPEN1  Serial3
 #define SERIAL_PORT_HARDWARE        Serial
 #define SERIAL_PORT_HARDWARE1       Serial1
 #define SERIAL_PORT_HARDWARE2       Serial2