CVE-2026-72228 batman-adv: frag: fix primary_if leak on failed linearization

In the Linux kernel, the following vulnerability has been resolved: batman-adv: frag: fix primaryif leak on failed linearization If the skb has a fraglist, it must be linearized before it can be split using skbsplit. But when this step failed, it must not only free the skb but also take care of t...