Make Haiku headers a bit more friendly to binding generators by:
- Giving some `enum`s names (especially those that appear in
default arguments).
- Converting an internal `inline` function into a macro so that
the result could be evaluated in compile time.
Change-Id: I770674ad8fa7b24ac30b6b447d52a4b4c2530b8a
Reviewed-on: https://review.haiku-os.org/c/haiku/+/6716
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
Reviewed-by: waddlesplash <waddlesplash@gmail.com>
