Refactor header files - includes should only declare, not define

lib/comms/comms.cpp

@@ -57,6 +57,7 @@ void _onUsbEvent0(void *arg, esp_event_base_t event_base, int32_t event_id,
 bool Comms::initComms(Config &c)
 {
     bool fine = false;
+#ifndef HELTEC
     if (c.listen_on_usb.equalsIgnoreCase("readline"))
     {
         // comms using readline plaintext protocol
@@ -68,13 +69,14 @@ bool Comms::initComms(Config &c)
 
         fine = true;
     }
+#endif
 
     if (c.listen_on_serial0.equalsIgnoreCase("readline"))
     {
         // comms using readline plaintext protocol
-        Comms0 = new ReadlineComms("UART0", Serial0);
-        Serial0.onReceive(_onReceive0, false);
-        Serial0.begin(115200);
+        Comms0 = new ReadlineComms("UART0", SERIAL0);
+        SERIAL0.onReceive(_onReceive0, false);
+        SERIAL0.begin(115200);
 
         Serial.println("Initialized communications on Serial0 using readline protocol");
     }

lib/comms/comms.h

@@ -5,6 +5,12 @@
 #include <HardwareSerial.h>
 #include <config.h>
 
+#ifdef HELTEC
+#define SERIAL0 Serial
+#else
+#define SERIAL0 Serial0
+#endif
+
 enum MessageType
 {
     WRAP = 0,
@@ -69,7 +75,7 @@ struct Comms
 
 struct NoopComms : Comms
 {
-    NoopComms() : Comms("no-op", Serial0) {};
+    NoopComms() : Comms("no-op", SERIAL0) {};
 
     virtual bool send(Message &) { return true; };
     virtual void _onReceive() {};