Without this, update_textures may not pick up the new pipe_resource.
It is actually update_textures that should check
stObj->sampler_view->texture != stObj->pt, but let's follow st_TexImage
and others for now.
/* FIXME create a non-default sampler view from the pipe_surface? */
pipe_resource_reference(&stObj->pt, ps->texture);
+ pipe_sampler_view_reference(&stObj->sampler_view, NULL);
pipe_resource_reference(&stImage->pt, stObj->pt);
stObj->width0 = ps->width;