CMake config: Fix CMAKE_MODULE_PATH getting erased
CMAKE_MODULE_PATH is getting cleared in client code after find_package(Paraview)
Fix it by renaming CMAKE_MODULE_PATH_save to CMAKE_MODULE_PATH_save_pv
I suspect something similar is done for VTK and that it overwrites the Paraview one.
This regression is due to !2971 (merged)
cc @ben.boeckel
Edited by Julien Schueller