This pkg's debian files and thus debian/patches/* are licensed under GPL-3.0+.
The patch(es) modifying the .h and .c files that end up in the binaries
possibly make them licensed under GPL-3+ and MPL-2. Please change the
debian/patches license so that they keep being distributable under MPL-2 because
projects using this as a dependency will probably not expect the GPL-3+ part.