seg6: fix the iif in the IPv6 socket control block
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v4.14.258 by commit b16d412e5f79734033df04e97d7ea2f50a8e9fe3, it was introduced in version v4.14.98 by commit c630ec8bdadae9d557b1ceb9d6c06e149108a0d4. For more details please see the references link.