Fix empty cpp warning

code/nel/src/3d/vertex_buffer_heap.cpp

@@ -25,6 +25,8 @@ using namespace NLMISC;
 #define new DEBUG_NEW
 #endif
 
+void vertex_buffer_heap_dummy_cpp() { }
+
 // This code is not used actually and doesn't compile
 // just preproc comment it
 #if 0