rygel-audio-item: Call the base class in apply_didl_lite
rygel-audio-item: Call the base class in apply_didl_lite

Otherwise the didl lite is not applied to the parents members.

https://bugzilla.gnome.org/show_bug.cgi?id=737867

GNOME/rygel,Tarnyko/rygel,Tarnyko/rygel,GNOME/rygel,GNOME/rygel