Snippets for argtable2 2.13 from Fedora s390x

Sourced from https://kojipkgs.fedoraproject.org/packages/argtable/2.13/35.fc45/data/logs/s390x/build.log.

• argtable2.c:97:6: warning: ‘dump_longoptions’ defined but not used [-Wunused-function]
     97 | void dump_longoptions(struct longoptions* longoptions)
        |      ^~~~~~~~~~~~~~~~