The part in createPlane() that exports a dma buffer from a video device
will be used directly by the FrameBuffer interface. Break it out to a
separate function.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>