[RFC v2 05/11] block: add infra to handle dmabuf tokens

[Anuj gupta]

> +void blk_mq_dma_map_move_notify(struct blk_mq_dma_token *token)
> +{
> +       blk_mq_dma_map_remove(token);
> +}
this needs to be exported as it is referenced from the nvme-pci driver,
otherwise we get a build error