tests/qtest/ac97-test: add up-/downsampling tests

tests/qtest/ac97-test: add up-/downsampling tests

Test if the audio subsystem can handle extreme up- and down-
sampling ratios like 44100/1 and 1/44100. For some time these
used to trigger QEMU aborts. The test was taken from
https://gitlab.com/qemu-project/qemu/-/issues/71 where it was
used to demonstrate a very different issue.

Suggested-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Volker Rümelin <vr_qemu@t-online.de>
Message-Id: <20230520113313.5177-1-vr_qemu@t-online.de>
Signed-off-by: Thomas Huth <thuth@redhat.com>