Clean up meson options
Lots of projects have been dropping the
enable- prefixes. gtk has no prefix (e.g.
build- prefix (
build-tests) or an
enable- prefix (for all the backends, colord, etc.).
It also still uses true/false for the boolean options, but yes/no/auto for the tristate options (instead of true/false/auto, which other projects seem to get ported to, and I favor a lot).
Would be good to get this cleaned up and streamlined with other gnome projects.