Sometimes the virtio_gpu in guest_vm doesn't pass the zero coord_x/y for the
displayed framebuffer. In such case the offset should be calibrated for pixman_image/dmabuf
so that it can display the image from the correct image.
Tracked-On: #7988
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Peng Sun <peng.p.sun@linux.intel.com>