blk: Use a macro for the typical block size

Avoid using the magic number 512 directly.

Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/nvme/nvme.c b/drivers/nvme/nvme.c
index 20dc910..c39cd41 100644
--- a/drivers/nvme/nvme.c
+++ b/drivers/nvme/nvme.c
@@ -906,7 +906,7 @@
 
 		/* The real blksz and size will be set by nvme_blk_probe() */
 		ret = blk_create_devicef(udev, "nvme-blk", name, UCLASS_NVME,
-					 -1, 512, 0, &ns_udev);
+					 -1, DEFAULT_BLKSZ, 0, &ns_udev);
 		if (ret)
 			goto free_id;