STYLE: use auto with vtkSmartPointer

...s/graphics/runTimePostProcessing/fieldVisualisationBase.C

...ects/graphics/runTimePostProcessing/functionObjectCloud.C

...jects/graphics/runTimePostProcessing/functionObjectLine.C

...ts/graphics/runTimePostProcessing/functionObjectSurface.C

...nObjects/graphics/runTimePostProcessing/geometrySurface.C

...functionObjects/graphics/runTimePostProcessing/pathline.C

...ts/graphics/runTimePostProcessing/runTimePostProcessing.C

src/functionObjects/graphics/runTimePostProcessing/scene.C

src/functionObjects/graphics/runTimePostProcessing/surface.C

src/functionObjects/graphics/runTimePostProcessing/text.C