CLSA-2026-1784715279 hplip: Fix of CVE-2026-14544

CVE-2026-14544: fix integer overflow in the hpcups PCLm encapsulation path PCLmGenerator::Encapsulate, an incomplete-fix follow-up to CVE-2026-8631 backport of the Red Hat fix from hplip-3.21.2-6.el98.5...