Fix warning in vtkChartXYZ
Fix warning in vtkChartXYZ

This fixes a shadowed variable warning in vtkChartXYZ.

Change-Id: Ia9d0aec4f64760cef13d54e534ff7b11d015051a

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