Merge branch 'nd/fbsd-lazy-mtime' into maint

FreeBSD can lie when asked mtime of a directory, which made the untracked cache code to fall back to a slow-path, which in turn caused tests in t7063 to fail because it wanted to verify the behaviour of the fast-path. * nd/fbsd-lazy-mtime: t7063: work around FreeBSD's lazy mtime update feature