MFC r322812:

Avoid TCP log messages which are false positives.

The check for timestamps are too early to handle SYN-ACK correctly.
So move it down after the corresponing processing has been done.

MFC r322813:

Avoid TCP log messages which are false positives.

This is https://svnweb.freebsd.org/changeset/base/322812, just for
alternate TCP stacks.

PR: 216832
Obtained from: antonfb@hesiod.org