[debian] building bundled talloc/tevent/tdb libs out of main samba sources

[Michael Tokarev]

Hi!

After a few times dealing with incompatibilities of older talloc/tevent/tdb
libs with new samba and shipping stuff for debian backports and other older
distributions, I decided to give it a try: to build these 3 bundled libs out
of samba source, without using separate tarballs (which also lacks git
history).

The result is rather simple, speaking for the packaging it's available at
https://salsa.debian.org/samba-team/samba/-/merge_requests/64 - 3 commits
importing packaging for tdb, tevent and talloc libs, one by one.

The only downsides of this are 2:

1. this is not supported by samba upstream directly (I had to patch
    lib/{talloc,tevent,tdb}/wscript a little bit)

2. these 3 bundled libs will be recompiled more often than it's
    actually needed, since they don't change with every samba
    release, and especially with every samba packaging release.

But speaking of maintaining this stuff, and (re)building for older
distributions, this is definitely a significant simplification.

Speaking of the resulting binary packages, - nothing really changed,
the set of packages is the same as before, with the same versions,
except packages for the bundled libs has got an extra version suffix
after samba source version, just like ldb subpackages.

I don't plan to make these to be "internal to samba" in any way, the
binary packages remains independent from samba.  But since their
development happens within the samba source, I see no good reason
to package them separately.  If upstream chooses to split them into
its own source repositories, we can easily resurrect the separate
source packages.

I remember the samba team had its own view on how packaging should be
done downstream, so I thought I'd ask before pushing this.

What do you think?

Thanks,

/mjt