Fix paraview.vtk Python modules to use vtk.* instead

As we changed the way Python modules from VTK are
integrated we had to change import path to properly
refer to the module that are in vtk package.

Change-Id: I58697c71a20c8e43f2e7e84b4f00fd090b114512
Merge topic 'fix-python-cmake-rules' into next

bd9ba7f Fix paraview.vtk Python modules to use vtk.* instead