bug#74367: [PATCH] c-ts-mode.el: Adjust doc about how to change default modes

[Stefan Kangas]

Stefan Monnier via "Bug reports for GNU Emacs, the Swiss army knife of
text editors" <bug-gnu-emacs@gnu.org> writes:

> Tags: patch
>
> The doc of `c-ts-mode.el` currently recommends things we deprecate.
> The patch below fixes this.
>
> I think this can go into `emacs-30`, but I believe Eli prefers we leave
> this alone there, so I guess it would go to `master`.  If we can install
> at least part of it into `emacs-30` (such as the removal of the
> recommendation to `require` or the suggestion to use the obsolete
> `c-or-c++-ts-mode`), I'll happily split it.

FWIW, I agree that we should at least remove the recommendation to use
`require` on emacs-30, as it encourages bad habits and contributes to an
already poor understanding of autoloading among users.