bug#80267: CC Mode 5.35.2 (C/*l); C mode comment in signature indentation regression

[Ulrich M. <ul...@ge...>]

Bisection points to this commit as the culprit:

https://cgit.git.savannah.gnu.org/cgit/emacs.git/commit/?id=555ec43a32ea8f3675c5a9d73ca30609eeaa9013
commit 555ec43a32ea8f3675c5a9d73ca30609eeaa9013
Author: Alan Mackenzie <ac...@mu...>
Date:   Thu Mar 27 10:24:48 2025 +0000

    C++ Mode: Fix some indentation bugs.  FIxes bug#19867