[musl] High-level C23 process requests

[Rich Felker <dalias@libc.org>]

The C23 patches have gotten to be something of a sprawl of threads of
various review and revision work, disagreements from minor to major,
etc., and I'd like to make a couple requests for keeping this
managable to myself and other list participants:

1. Generally, we don't do the LKML-style thing of sending N related
   patches as N replies to a thread. This is really unmanagable for
   folks' inboxes, and a few people have expressed that already to me
   out-of-band. Patches are best sent in MIME form, with a set of
   related patches all attached to a single email. This makes it a lot
   easier to discuss with context that crosses individual patch
   boundaries, and for folks not interested in them to ignore them. It
   also makes it possible to keep the v2, etc. in the same thread so
   context is preserved (which isn't a hard rule or anything, but
   might help keep things organized here).

2. Extension (or "optional") functionality that's not a C23
   conformance requirement should be clearly marked as such and
   proposed separately, ideally after C23 work is merged so that
   there's not so much cognitive load here. This is the only way
   that's fair to our community to be able to engage in any sort of
   process about whether such changes move forward. Normally, when
   this kind of change is proposed, it's in isolation and clearly
   visible for folks to weigh in on, but that does not work when it's
   bundled with changes which would be automatically acceptable in
   principle as conformance requirements.