Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.Approved by: re (implicit)Sponsored by: The FreeBSD Foundation
MFC: r251368, r251382: Match the options of the kernel.
MFC: r236592 r236593 r236594 r236620 r236621 r236622 r236637 r237794: filemon(4)
Add a regression test for filemon(4) [r236592].