Commit d52c454a "contrib: add vhost-user-gpu" and "c68082c4
virtio-gpu: split virtio-gpu-pci & virtio-vga" created headers with
unusual header guard symbols.  Clean them up

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190607141321.9726-1-armbru@redhat.com>