nvme-pci: use standard block status symbolic names

Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/host/pci.c

@@ -762,7 +762,7 @@ static blk_status_t nvme_setup_prp_simple(struct nvme_dev *dev,
 	cmnd->dptr.prp1 = cpu_to_le64(iod->first_dma);
 	if (bv->bv_len > first_prp_len)
 		cmnd->dptr.prp2 = cpu_to_le64(iod->first_dma + first_prp_len);
-	return 0;
+	return BLK_STS_OK;
 }
 
 static blk_status_t nvme_setup_sgl_simple(struct nvme_dev *dev,
@@ -780,7 +780,7 @@ static blk_status_t nvme_setup_sgl_simple(struct nvme_dev *dev,
 	cmnd->dptr.sgl.addr = cpu_to_le64(iod->first_dma);
 	cmnd->dptr.sgl.length = cpu_to_le32(iod->dma_len);
 	cmnd->dptr.sgl.type = NVME_SGL_FMT_DATA_DESC << 4;
-	return 0;
+	return BLK_STS_OK;
 }
 
 static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
@@ -844,7 +844,7 @@ static blk_status_t nvme_map_metadata(struct nvme_dev *dev, struct request *req,
 	if (dma_mapping_error(dev->dev, iod->meta_dma))
 		return BLK_STS_IOERR;
 	cmnd->rw.metadata = cpu_to_le64(iod->meta_dma);
-	return 0;
+	return BLK_STS_OK;
 }
 
 /*