compositor: print usage to stdout on success (not stderr) - this time really Fix all the other printfs too. https://gitlab.freedesktop.org/wayland/weston/issues/112 Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net> Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>