Previously the display pass was used from the KernelFilm, which
requires a device update between display pass modification and GPU
display update. Such update is avoidable by using display pass from
film.

With the current state of the code should not be user level changes,
but this allows to have more instant display pass update when GPU
display is used for non-interactive rendering.

Possible improvement would be to separate display pass from node graph
so that change to film's display pass does not cause device_update.