drm/virtio: Pass correct device to dma_sync_sgtable_for_device()

The "vdev->dev.parent" should be used instead of "vdev->dev" as a device
for which to perform the DMA operation in both
virtio_gpu_cmd_transfer_to_host_2d(3d).

Because the virtio-gpu device "vdev->dev" doesn't really have DMA OPS
assigned to it, but parent (virtio-pci or virtio-mmio) device
"vdev->dev.parent" has. The more, the sgtable in question the code is
trying to sync here was mapped for the parent device (by using its DMA OPS)
previously at:
virtio_gpu_object_shmem_init()->drm_gem_shmem_get_pages_sgt()->
dma_map_sgtable(), so should be synced here for the same parent device.

Fixes: b5c9ed70 ("drm/virtio: Improve DMA API usage for shmem BOs")
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230224153450.526222-1-olekstysh@gmail.com