dbus: Remove duplication of object methods/signals/properties

dbus: Remove duplication of object methods/signals/properties

There is no need to duplicate the method/signal/property arrays that
were registered for objects. The registration was using static arrays
on methods/signals/properties in all places and we can as well use
those throughout without having to allocate memory and copy all the
entries for every object. This reduces number of allocations and
amount of unnecessary code quite a bit.