bug#56598: Make cdl.el obsolete

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: Stefan Kangas <stefan@marxist.se>,  56598@debbugs.gnu.org
> Date: Sat, 16 Jul 2022 12:18:35 +0200
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > I see nothing wrong with supporting netCDF in Emacs.  Adding features
> > to cdl.el will be welcome, but having front-end commands for the
> > netCDF tools is already useful enough.
> 
> For the record, I'm in favour of obsoleting it.  That cdl.el has
> remained in the same useless state for three decades demonstrates that
> it's unlikely to ever be extended by anybody.

This is not what "obsolete" is about, in Emacs.