Since busname units are only useful with kdbus, they weren't actively
used. This was dead code, only compile-tested. If busname units are
ever added back, it'll be cleaner to start from scratch (possibly reverting
parts of this patch).
# service.h
# socket.c
# socket.h
-# busname.c
-# busname.h
# bus-policy.c
# bus-policy.h
# target.c
# dbus-service.h
# dbus-socket.c
# dbus-socket.h
-# dbus-busname.c
-# dbus-busname.h
# dbus-target.c
# dbus-target.h
# dbus-device.c