minor change to be more compatible with some opengl hardware
minor change to be more compatible with some opengl hardware

Change-Id: Ie21b224a110c9e81ebbc0f301ee3d1438e14204c

mspark93/VTK,demarle/VTK,SimVascular/VTK,jmerkow/VTK,jmerkow/VTK,sankhesh/VTK,candy7393/VTK,candy7393/VTK,keithroe/vtkoptix,demarle/VTK,keithroe/vtkoptix,sankhesh/VTK,gram526/VTK,mspark93/VTK,msmolens/VTK,johnkit/vtk-dev,demarle/VTK,berendkleinhaneveld/VTK,mspark93/VTK,sankhesh/VTK,mspark93/VTK,ashray/VTK-EVM,sankhesh/VTK,gram526/VTK,candy7393/VTK,hendradarwin/VTK,candy7393/VTK,jmerkow/VTK,demarle/VTK,demarle/VTK,msmolens/VTK,keithroe/vtkoptix,candy7393/VTK,candy7393/VTK,hendradarwin/VTK,SimVascular/VTK,demarle/VTK,jmerkow/VTK,SimVascular/VTK,jmerkow/VTK,johnkit/vtk-dev,sankhesh/VTK,gram526/VTK,ashray/VTK-EVM,ashray/VTK-EVM,berendkleinhaneveld/VTK,jmerkow/VTK,msmolens/VTK,gram526/VTK,berendkleinhaneveld/VTK,SimVascular/VTK,msmolens/VTK,sumedhasingla/VTK,keithroe/vtkoptix,gram526/VTK,SimVascular/VTK,jmerkow/VTK,sankhesh/VTK,sumedhasingla/VTK,mspark93/VTK,sumedhasingla/VTK,hendradarwin/VTK,berendkleinhaneveld/VTK,ashray/VTK-EVM,msmolens/VTK,jmerkow/VTK,ashray/VTK-EVM,SimVascular/VTK,msmolens/VTK,hendradarwin/VTK,SimVascular/VTK,gram526/VTK,msmolens/VTK,johnkit/vtk-dev,keithroe/vtkoptix,berendkleinhaneveld/VTK,mspark93/VTK,sumedhasingla/VTK,hendradarwin/VTK,hendradarwin/VTK,johnkit/vtk-dev,gram526/VTK,mspark93/VTK,msmolens/VTK,ashray/VTK-EVM,berendkleinhaneveld/VTK,keithroe/vtkoptix,keithroe/vtkoptix,johnkit/vtk-dev,ashray/VTK-EVM,sumedhasingla/VTK,candy7393/VTK,sankhesh/VTK,gram526/VTK,sumedhasingla/VTK,johnkit/vtk-dev,sumedhasingla/VTK,keithroe/vtkoptix,berendkleinhaneveld/VTK,mspark93/VTK,sumedhasingla/VTK,johnkit/vtk-dev,demarle/VTK,demarle/VTK,ashray/VTK-EVM,sankhesh/VTK,hendradarwin/VTK,SimVascular/VTK,candy7393/VTK