Add info about dependencies
Add info about dependencies

I just set up a flatpak build from scratch on an F28
machine. This is what I had to install to get a build
going.

Closes: #2184
Approved by: alexlarsson

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