tools/virtio: more stubs

As usual, add more stubs to fix test build after main
codebase changes.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c
index db3437c..67873c3 100644
--- a/tools/virtio/virtio_test.c
+++ b/tools/virtio/virtio_test.c
@@ -11,6 +11,7 @@
 #include <sys/types.h>
 #include <fcntl.h>
 #include <stdbool.h>
+#include <linux/virtio_types.h>
 #include <linux/vhost.h>
 #include <linux/virtio.h>
 #include <linux/virtio_ring.h>