Fix of 'dbus-daemon can only handle 64 simultaneous connections on Windows'.

[Slightly modified by -rh]

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=71297
Reviewed-by: Ralf Habacker <ralf.habacker@freenet.de>
Reviewed-by: Simon McVittie <simon.mcvittie@collabora.co.uk>