WIP: Make Linphone 3.2.4 build with upstream Antlr 3.4

Open username-removed-741444 requested to merge anrp/fdroiddata:linphone into master

As the title says. I created a repo with a per-version-tag here on gitlab for Antlr3, since the upstream repo seems to be missing the exact state of the release tar.gz. Not sure if that's the best way to do it (should the metadata just download & verify the tar.gz?)