bug#62339: cc-mode fontifies variables incorrectly when const follows type

[Eli Zaretskii]

> From: Daniel Colascione <dancol@dancol.org>
> Cc: 62339@debbugs.gnu.org
> Date: Wed, 22 Mar 2023 10:19:55 -0400
> 
> This problem reproduces for me on latest master with emacs -Q:
> 
> ```
> TEST(Foo, Bar) {
>   NamedTemporaryDirectory const test_directory;
> }
> ```

Thanks.  What I see with Emacs built from master is that
test_directory in the above example gets font-lock-type-face in
c++-mode (but not in c-mode).  With Emacs built from emacs-29, both
modes produce correct fontification.

Alan, can you please look into this?