[m-dev.] New stable release

[M McDonough]

On Mon, 17 Jan 2022, Julien Fischer wrote:

> It's high time we had a new stable release since the existing one is
> now a couple of years old.  I propose to create the release branch
> towards the end of this week unless anyone has particularly strong
> objections to doing so.  We'll try (this time) to have another stable
> release in six months time, so anything that doesn't make it into
> this release can go into the next one.

It might be worth noting that in the new release Mercury on Sparc64
has been fixed, and with the sem-recent Boehm update it runs on
OpenBSD Sparc64.

Or maybe that's not worth noting, not sure how many people out there
are using Sparc64 anymore.