contrib: add vhost-user-gpu

Add a vhost-user gpu backend, based on virtio-gpu/3d device. It is
associated with a vhost-user-gpu device.

Various TODO and nice to have items:
- multi-head support
- crash & resume handling
- accelerated rendering/display that avoids the waiting round trips
- edid support

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20190524130946.31736-6-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
diff --git a/Makefile.objs b/Makefile.objs
index d749141..be7ad2f 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -123,6 +123,7 @@
 vhost-user-blk-obj-y = contrib/vhost-user-blk/
 rdmacm-mux-obj-y = contrib/rdmacm-mux/
 vhost-user-input-obj-y = contrib/vhost-user-input/
+vhost-user-gpu-obj-y = contrib/vhost-user-gpu/
 
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