BUG: revert last change, this breaks paraview build.

vtk/CMakeLists.txt

@@ -49,6 +49,10 @@ SET_SOURCE_FILES_PROPERTIES(
   WRAP_EXCLUDE
   )
 
+SET(VTK_BINARY_DIR "${Xdmf_BINARY_DIR}/vtk")
+INCLUDE(${VTK_CMAKE_DIR}/vtkExportKit.cmake)
+VTK_EXPORT_KIT("Xdmf" "XDMF" "${Xdmf_SRCS}")
+
 SET(VTK_BINARY_DIR "${Xdmf_BINARY_DIR}/vtk")
 # if vtk was found include the use vtk file
 IF (VTK_FOUND)