Fix a small bug in the tcp_log_id where the bucket
was unlocked and yet the bucket-unlock flag was not
changed to false. This can cause a panic if INVARIANTS
is on and we go through the right path (though rare).
This fixes the correct bug :)

Reported by: syzbot+179a1ad49f3c4c215fa2@syzkaller.appspotmail.com
Reviewed by: tuexen@