Add more Debian extensions to filehighlight.ini

[sergey-dryabzhinsky]

Proposed changes

Add mode debian file extensions

• ddeb
• udeb

• Resolves: Add more debian file extensions to file highlights  #5108

Checklist

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• I have referenced the issue(s) resolved by this PR (if any)
• I have signed-off my contribution with git commit --amend -s
• Lint and unit tests pass locally with my changes (make indent && make check)
• I have added tests that prove my fix is effective or that my feature works
• I have added the necessary documentation (if appropriate)

[zyv]

@mc-worker, apparently on the latest Fedora they redefined strchr as const char * also for C, not only for C++. But the code itself is quite disgusting in that it modifies original strings through derived pointers. Could you please help to rewrite it in some clear and simple way without stripping qualifiers to fix the CI?

path.c: In function 'vfs_path_from_str_deprecated_parser':
path.c:360:20: error: assignment discards 'const' qualifier from pointer target type [-Werror=discarded-qualifiers]
  360 |         url_params = strchr (op, ':');  // skip VFS prefix

[mc-worker]

apparently on the latest Fedora they redefined strchr as const char * also for C, not only for C++.

This is C23. I read about that in the Gnulib mailing list:
https://lists.gnu.org/archive/html/bug-gnulib/2025-11/msg00220.html.

Could you please help to rewrite it in some clear and simple way without stripping qualifiers to fix the CI?

I have a cleanup branch with few commits. I'll make it there.

[zyv]

/rebase

[zyv]

Thank you for your contribution!