FSDG sane-frontends lib/snprintf.c is under an Artistic License

As per https://trisquel.info/en/issues/11793 (see #7 (closed) and #8 (closed) also).

Legimet's commit wasn't accepted - investigate / rework

mentioned in issue #8 (closed)

mentioned in commit 935c57fe

trisquel/package-helpers!12 (merged) contains 935c57fe

mentioned in commit aklis/package-helpers@935c57fe

Status changed to closed

mentioned in commit mixalis/package-helpers@935c57fe