bd277cec42
Adapt OpenBSD pf's "sloopy" TCP state machine which is useful for Direct Server Return mode, where not all packets would be visible to the load balancer or gateway. This commit should be reverted when we merge future pf versions. The benefit it would provide is that this version does not break any existing public interface and thus won't be a problem if we want to MFC it to earlier FreeBSD releases. Discussed with: mlaier Obtained from: OpenBSD Sponsored by: iXsystems, Inc.