tests/avocado/virtio-gpu: Cancel test if drm rendering is not available

The test_vhost_user_vga_virgl test currently fails on some CI
machines with:

 qemu-system-x86_64: egl: no drm render node available
 qemu-system-x86_64: egl: render node init failed

The other test in this file already checks whether there is
an error while starting QEMU - we should do the same for the
test_vhost_user_vga_virgl test, too.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230530180330.48722-1-thuth@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
1 file changed