tests/functional: bail early if vkmark hangs The message: MESA-VIRTIO: debug: stuck in fence wait with iter at %d Seems to occur more often on debug builds. Rather than waiting for our long timeout to hit we might as well bail as soon as we see the message. Reviewed-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20250304222439.2035603-5-alex.bennee@linaro.org>