Make AX.25, DMR, P25, NXDN and FM selectable at compile time.

DMRRX.cpp

@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2020 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -17,6 +17,9 @@
  */
 
 #include "Config.h"
+
+#if defined(MODE_DMR)
+
 #include "Globals.h"
 #include "DMRRX.h"
 
@@ -68,3 +71,5 @@ void CDMRRX::reset()
   m_slot2RX.reset();
 }
 
+#endif
+