dm: block: Rename device number member dev to devnum

This is a device number, and we want to use 'dev' to mean a driver model
device. Rename the member.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
diff --git a/cmd/reiser.c b/cmd/reiser.c
index a717956..cbdad36 100644
--- a/cmd/reiser.c
+++ b/cmd/reiser.c
@@ -48,7 +48,7 @@
 	    filename = argv[3];
 	}
 
-	dev = dev_desc->dev;
+	dev = dev_desc->devnum;
 	PRINTF("Using device %s %d:%d, directory: %s\n", argv[1], dev, part, filename);
 
 	reiserfs_set_blk_dev(dev_desc, &info);
@@ -126,7 +126,7 @@
 	if (part < 0)
 		return 1;
 
-	dev = dev_desc->dev;
+	dev = dev_desc->devnum;
 
 	printf("Loading file \"%s\" from %s device %d%c%c\n",
 		filename, argv[1], dev,