Python init config used COPYONLY instead of ONLY.

The file vtkWrapperInit.data.in has a macro that must be expanded,
so it requires @ONLY instead of COPYONLY.

Change-Id: Id6a0c9ab101ecaaf53020a67bded3a1a78005f7f
Merge topic 'wrapper-init-only' into master

9d8e8a76 Python init config used COPYONLY instead of ONLY.