The Appstream metadata file introduced in commit
335612cfa4
has been submitted as licensed under the CC0-1.0 license. People
generally use the CC0-1.0 to put the file in the "public domain", but
this isn't actually possible in lots of countries, so the file ends up
being licensed under CC0's fallback permissive license; unfortunately,
the fallback license contains some terms that are seen as problematic to
some (notably, Fedora has recently decided to consider the license
pretty much non-free).
As foot is already MIT-licensed, and since this license is in the list
of allowed [metadata licenses], this patch changes the license of the
metadata file from CC0-1.0 to MIT.
[metadata licenses]: https://freedesktop.org/software/appstream/docs/chap-Metadata.html#tag-metadata_license
