NVMe: Pass the nvme_dev to nvme_free_prps and nvme_setup_prps

We were passing the nvme_queue to access the q_dmadev for the
dma_alloc_coherent calls, but since we moved to the dma pool API,
we really only need the nvme_dev.

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>