Zero unexpected ATF test failures on amd64

[Andreas Gustafsson <gson%gson.org@localhost>]

Hi all,

NetBSD-current has again completed an ATF test run with zero
unexpected failures on real amd64 hardware:

  http://www.gson.org/netbsd/bugs/build/amd64-baremetal/commits-2019.06.html#2019.06.23.22.48.15

Let's try to keep it this way at least until NetBSD-9 has been
branched. :)
-- 
Andreas Gustafsson, gson%gson.org@localhost