New review comment by dkosovic on void-packages repository

https://github.com/void-linux/void-packages/pull/23646#discussion_r459187118

Comment:
The current Debian package has a patch that does that, so can confirm it should work with that location.

The next upstream version will use `/usr/share/dbus-1/system.d` by default with commit https://github.com/nm-l2tp/NetworkManager-l2tp/commit/1fb9197b628f4b010e515a49b55a2d20ed18a9cf.