COMP: Silence warnings about unused variables
COMP: Silence warnings about unused variables

Employed vtkNotUsed() macro to silence some warnings.

keithroe/vtkoptix,hendradarwin/VTK,johnkit/vtk-dev,johnkit/vtk-dev,cjh1/VTK,jmerkow/VTK,SimVascular/VTK,jmerkow/VTK,SimVascular/VTK,sumedhasingla/VTK,collects/VTK,biddisco/VTK,msmolens/VTK,cjh1/VTK,SimVascular/VTK,mspark93/VTK,candy7393/VTK,berendkleinhaneveld/VTK,hendradarwin/VTK,mspark93/VTK,ashray/VTK-EVM,msmolens/VTK,cjh1/VTK,sankhesh/VTK,gram526/VTK,ashray/VTK-EVM,sankhesh/VTK,sumedhasingla/VTK,sumedhasingla/VTK,msmolens/VTK,keithroe/vtkoptix,keithroe/vtkoptix,hendradarwin/VTK,candy7393/VTK,demarle/VTK,jmerkow/VTK,msmolens/VTK,sumedhasingla/VTK,demarle/VTK,jmerkow/VTK,aashish24/VTK-old,aashish24/VTK-old,demarle/VTK,mspark93/VTK,sumedhasingla/VTK,msmolens/VTK,msmolens/VTK,keithroe/vtkoptix,berendkleinhaneveld/VTK,jmerkow/VTK,gram526/VTK,mspark93/VTK,johnkit/vtk-dev,mspark93/VTK,hendradarwin/VTK,demarle/VTK,johnkit/vtk-dev,ashray/VTK-EVM,SimVascular/VTK,jmerkow/VTK,aashish24/VTK-old,johnkit/vtk-dev,sumedhasingla/VTK,sankhesh/VTK,sumedhasingla/VTK,jmerkow/VTK,gram526/VTK,keithroe/vtkoptix,hendradarwin/VTK,hendradarwin/VTK,candy7393/VTK,berendkleinhaneveld/VTK,gram526/VTK,candy7393/VTK,demarle/VTK,candy7393/VTK,sumedhasingla/VTK,jmerkow/VTK,biddisco/VTK,demarle/VTK,berendkleinhaneveld/VTK,collects/VTK,msmolens/VTK,sankhesh/VTK,sankhesh/VTK,gram526/VTK,berendkleinhaneveld/VTK,hendradarwin/VTK,keithroe/vtkoptix,mspark93/VTK,candy7393/VTK,collects/VTK,aashish24/VTK-old,aashish24/VTK-old,berendkleinhaneveld/VTK,sankhesh/VTK,biddisco/VTK,msmolens/VTK,collects/VTK,biddisco/VTK,candy7393/VTK,candy7393/VTK,ashray/VTK-EVM,gram526/VTK,gram526/VTK,cjh1/VTK,johnkit/vtk-dev,demarle/VTK,biddisco/VTK,collects/VTK,sankhesh/VTK,SimVascular/VTK,cjh1/VTK,gram526/VTK,SimVascular/VTK,biddisco/VTK,keithroe/vtkoptix,mspark93/VTK,mspark93/VTK,SimVascular/VTK,johnkit/vtk-dev,ashray/VTK-EVM,demarle/VTK,keithroe/vtkoptix,collects/VTK,cjh1/VTK,ashray/VTK-EVM,aashish24/VTK-old,berendkleinhaneveld/VTK,SimVascular/VTK,biddisco/VTK,ashray/VTK-EVM,ashray/VTK-EVM,sankhesh/VTK