Remove unnecessary icon redefinition.
Remove unnecessary icon redefinition.

This cleans up the code and causes the "hide" icons to default to the
same icons they normally use. It is the exact same icon that was being
passed in before, only now the corresponding one will also be used
instead of Blender's driver default icon.

prman-pixar/RenderManForBlender,prman-pixar/RenderManForBlender,adminradio/RenderManForBlender