* test-suite/tests/sxml.fold.test:
* test-suite/tests/sxml.ssax.test:
* test-suite/tests/sxml.transform.test:
* test-suite/tests/sxml.xpath.test:
* test-suite/tests/texinfo.docbook.test:
* test-suite/tests/texinfo.serialize.test:
* test-suite/tests/texinfo.string-utils.test:
* test-suite/tests/texinfo.test: Update licenses to GPL or LGPL 3+, and
update copyright holders to be FSF (where that is the case). Copyright
holders who are not FSF have their code in GPL/LGPL-compatible
licesnse.