regress: Add some tests with ~adns_if_noautosys

The test harness provides adns_if_noautosys by default (to make the
test .sys files more readable and less noisy, mostly).

But adns behaves rather differently with noautosys.  We should have
some more tests without it.  (The invocations of adnstest implied by
these new test cases produce obviously-wrong behaviour with an adns
which is lacking the TCP async connect API fix.)

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>