[Libosinfo] [osinfo-db PATCH] ubuntu: add Ubuntu 17.10 info

[Felipe Borges]

Could we have the variant data as well?

>From this download endpoint [0] I see that they are named

"Ubuntu 17.10 Desktop" and "Ubuntu 17.10 Server".

For context: we'd like to offer distro downloads from GNOME Boxes New
machine dialog (wizard) but unfortunately only Fedora has proper
variant names to identify medias as workstation, server, *netinstall,
etc... This way, so far, we're showing the real file base name instead
of a string based on the variant. See in action (video) [1].

I'd be happy to provide patches updating other Operating Systems if
that's desired.

Thanks,
Felipe.

[0] https://www.ubuntu.com/download/alternative-downloads
[1] https://webmshare.com/XQPma