v2:
- meson 0.40 requirement
- add_project_arguments() instead of add_global_arguments()
- use cc.get_define('static_assert')
- use config.set10 and config.set_quoted instead of manual handling
- more use of join_paths
- use files() for model quirks hwdb check
- update options to all state 'true' as default instead of variations of
  'true', 'enabled' and 'yes'

v3:
- drop -Wall -Wextra and -g, let meson set that with warning_level/debug build
- add meson files to EXTRA_DIST

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>