Add the new submodule to autogen.sh
Add the new submodule to autogen.sh

This is not perfect, but will make fresh checkouts work
as well as before.

Closes: #2121
Approved by: alexlarsson

matthiasclasen/flatpak,flatpak/flatpak,flatpak/flatpak,matthiasclasen/flatpak,flatpak/flatpak,matthiasclasen/flatpak,flatpak/flatpak,matthiasclasen/flatpak,flatpak/flatpak,matthiasclasen/flatpak