compositor: Avoid using weston_log() in weston_view_is_opaque()
As from commit b7e5f10b, weston_view_is_opaque() is called from debug_scene_graph_cb(), which on its own represents a (different) scope. By default, we already have a subscriber for the 'log' scope, which will cause a harmless, yet spurious, message.
Signed-off-by: Marius Vlad marius.vlad@collabora.com