message: The subdivision geometry cannot be released b/c we need the ref for UI
  The UI sliders in the app code are still modifying the geometry, so we
  can't release the app-side reference to the object. This fixes the
  subdivision tutorial crashing when run with the MPIOffloadDevice
diff: @@ -189,7 +189,6 @@ int main(int argc, const char **argv)
  OSPTestingGeometry subdivisionGeometry =
  ospTestingNewGeometry("subdivision_cube", "scivis");
  ospAddGeometry(world, subdivisionGeometry.geometry);
  - ospRelease(subdivisionGeometry.geometry);
  // add in a ground plane geometry
  ospAddGeometry(world, createGroundPlaneGeometry());
  @@ -276,6 +275,7 @@ int main(int argc, const char **argv)
  glfwOSPRayWindow->mainLoop();
  // cleanup remaining objects
  + ospRelease(subdivisionGeometry.geometry);
  ospRelease(world);
  ospRelease(renderer);
  