simple-dmabuf-drm: require zwp_linux_dmabuf_v1 v3

We effectively require it as we don't react to dmabuf_format,
only to dmabuf_modifiers, so there's a chance we may not get
the supported formats information at all.

Signed-off-by: Emilio Pozuelo Monfort <emilio.pozuelo@collabora.co.uk>
Reviewed-by: Daniel Stone <daniels@collabora.com>