Load debugpy when possible to allow python debugging in-program

qrenderdoc/Code/pyrenderdoc/pyrenderdoc_stub.cpp

@@ -72,6 +72,11 @@ extern "C" void ProcessDecRefQueue()
 {
 }
 
+extern "C" PyObject *DoFunctionCall(PyObject *object, PyObject *args)
+{
+  return PyObject_Call(object, args, NULL);
+}
+
 extern "C" RENDERDOC_EXPORT_API int _rd_python_minor_version()
 {
   return PY_MINOR_VERSION;