Remove ChemistryOpenGL2 from the OpenGL kit

None of the rest of Domains/Chemistry is in a kit, and its inclusion
into the OpenGL kit causes cyclic dependencies between IO, Rendering
and itself.

Domains/ChemistryOpenGL2/vtk.module

@@ -4,8 +4,6 @@ LIBRARY_NAME
   vtkDomainsChemistryOpenGL2
 DESCRIPTION
   OpenGL support for chemistry data
-KIT
-  VTK::OpenGL
 IMPLEMENTS
   VTK::DomainsChemistry
 DEPENDS