CLSA-2025-1760017744 Fix CVE(s): CVE-2025-6491

SECURITY UPDATE: fix NULL pointer dereference in SOAP with huge QName - debian/patches/CVE-2025-6491.patch: Add safeguard in ext/soap/soap.c to handle invalid XML node names produced by libxml2 with extremely large namespace prefixes - CVE-2025-6491...