lib: Fix warnings when D-Bus related properties change

When UPower would appear, or disappear, we'd get warnings like:
g_object_notify: object class 'UpDevice' has no property named 'g-name-owner'
or:
g_object_notify: object class 'UpClient' has no property named 'g-name-owner'

This was caused by the property proxying added in 7531dbda and 28438a76
being too lax about which properties it tried to proxy, which included
ones that didn't apply to the object types in question.

See https://bugs.freedesktop.org/show_bug.cgi?id=43001

https://bugs.freedesktop.org/show_bug.cgi?id=102350