message: don't always add the ISPC module when creating Device instances
diff: @@ -23,6 +23,7 @@ Version History
  arguments first before committing the device, to ensure it is committed
  in a valid state.
  - Fix issue with OSPRay ignoring tasking system thread count settings
  +- Fix issue where OSPRay always loaded the ISPC module, even if not required
  #### Known Issues:
  - None
  