xfrm: Fix skb double-free in xfrm_dev_direct_output()

In the Linux kernel, the following vulnerability has been resolved: xfrm: Fix skb double-free in xfrm_dev_direct_output() A return value other than 1 from local_out() means that the skb has been consumed or its ownership was transferred. xfrm_dev_direct_output() nevertheless frees the skb on this path, causing a double-free when netfilter drops the packet and invalidating any other owner. Return the local_out() result directly, matching the ownership handling in xfrm_output_resume().