fix oiiotool buglet
fix oiiotool buglet

jeremyselan/oiio,cwilling/oiio,micler/oiio,jeremyselan/oiio,OpenImageIO/oiio,lgritz/oiio,OpenImageIO/oiio,micler/oiio,sambler/oiio,lgritz/oiio,cwilling/oiio,mcanthony/oiio,scott-wilson/oiio,sambler/oiio,scott-wilson/oiio,YangYangTL/oiio,YangYangTL/oiio,jeremyselan/oiio,micler/oiio,bdeluca/oiio,sambler/oiio,micler/oiio,bdeluca/oiio,YangYangTL/oiio,cwilling/oiio,bdeluca/oiio,scott-wilson/oiio,scott-wilson/oiio,OpenImageIO/oiio,lgritz/oiio,sambler/oiio,mcanthony/oiio,bdeluca/oiio,mcanthony/oiio,YangYangTL/oiio,OpenImageIO/oiio,lgritz/oiio,mcanthony/oiio,cwilling/oiio