CMake: Override PARAVIEW_ENABLE_EMBEDDED_DOCUMENTATION
Fixes paraview build with Qt6 ;
its not enough to drop targets from /Documentation directory as done in !6274 (merged),
but also the define PARAVIEW_ENABLE_EMBEDDED_DOCUMENTATION must also be unset
else paraview's main.cxx tries to include ParaViewDocumentationInitializer.h which is not generated
Edited by Julien Schueller