CVE-2026-80901 ipvs: fix the checksum validations

In the Linux kernel, the following vulnerability has been resolved: ipvs: fix the checksum validations ipvsinicmpv6 is missing checksum validation for ICMPv6 packets from clients. In fact, as for TCP/UDP we should validate the checksum for ICMP packets only when we mangle the packets on MASQ or o...