The `dracut_install` is a misnomer, since the systemd integration test
suite is based on the original dracut's test suite, and not all the
references to dracut has been edited out. Let's fix that.
The logic to query test state was rather complex. I don't quite grok the point
of ret=$((ret+1))… But afaics, the precise result was always ignored by the
caller anyway.
oomd works way better with swap, so let's make the test less flaky by
configuring a swap device for it. This also allows us to drop the ugly
`cat`s from the load-generating script.
