cmake: update to `VTK_ENABLE_VR_COLLABORATION`

`VTK_ENABLE_OPENVR_COLLABORATION` was changed to
`VTK_ENABLE_VR_COLLABORATION` in VTK. Hence this change is needed.

Plugins/OpenVR/Plugin/CMakeLists.txt

@@ -61,7 +61,7 @@ if (PARAVIEW_OpenVR_Imago_Support)
       COMPILE_DEFINITIONS OPENVR_HAS_IMAGO_SUPPORT)
 endif()
 
-if (VTK_ENABLE_OPENVR_COLLABORATION)
+if (VTK_ENABLE_VR_COLLABORATION)
   set_property(SOURCE vtkPVOpenVRCollaborationClient.cxx APPEND PROPERTY
     COMPILE_DEFINITIONS OPENVR_HAS_COLLABORATION
     )