bug#59763: 29.0.60; Filling for c-ts-mode

[Eli Zaretskii <eliz@gnu.org>]

> From: Yuan Fu <casouri@gmail.com>
> Date: Thu, 1 Dec 2022 21:33:06 -0800
> 
> 
> IMO For c-ts-mode to be usable we need to have at least a basic filling
> function. Below is the function I have in my init.el, could someone have
> a look and see if it’s good? Alternatively we could copy out the comment
> and fill it in a temp buffer with c-mode, but I didn’t have the time to try
> it out and see how well it works.

Thanks.

From quick testing, I see a problem:

  . Visit dispnew.c and go to the comment that starts on line 324.  Delete
    the newline between the two lines of the comment, and invoke the
    function.  Observe how the first non-blank character of the comment's
    second line is aligned with the "/*" on the previous line, not with the
    text after "/*" as I'd expect.

Btw, this command should be bound to M-q in ts-c-mode.