vhost-user-gpu: skip VHOST_USER_GPU_UPDATE when !PIXMAN

This simply means that 2d drawing updates won't be handled, but 3d
should work.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
1 file changed