virtio fences were created with no fence context, which would make then
clash with an allocated fence context.
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Message-id: 1472660813-28219-2-git-send-email-gustavo@padovan.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>