drm-qemu: virtio sparse fix, MAINTAINERS updates.

* tag 'drm-qemu-20170110' of git://git.kraxel.org/linux:
  drm: flip cirrus driver status to "obsolete".
  drm: update MAINTAINERS for qemu drivers (bochs, cirrus, qxl, virtio-gpu)
  drm/virtio: fix framebuffer sparse warning