socket: make sure that the name for per-connection services are unique

socket: make sure that the name for per-connection services are unique

If a client connects to us repeatedly always using the same source port
and we instantiate a service for the incoming connection this might
clash with an old instance. Hence, include the connection number, the
same way we do it for AF_UNIX to make connections unique.

https://bugs.freedesktop.org/show_bug.cgi?id=45297