CVE-2021-25317: install /var/log/cups as 0700 root:sys instead of 0755 lp:sys
so the 'lp' user cannot plant symlinks that cupsd follows on log creation.
This matches the mode cupsd itself computes for the log directory
(0300|LogFilePerm with --with-log-file-perm=0600).
CVE-2025-58364: already addressed by Patch103 (upstream e58cba9d), shipped in
1:1.6.3-52.tuxcare.els5; no code change in this release.