Found that osxaudiosink could not be added standalone in gst-full build using -Dgst-full-elements=osxaudio:osxaudiosink because element registration was done at the plugin level. Now src/sink elements and deviceprovider have their individual registration. Copied/adapted from the alsa plugin. Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5419>