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/fs/fat/fat.c b/fs/fat/fat.c
index 47f077d..f87ddd7 100644
--- a/fs/fat/fat.c
+++ b/fs/fat/fat.c
@@ -100,7 +100,7 @@
 	if (part_get_info(dev_desc, part_no, &info)) {
 		if (part_no != 0) {
 			printf("** Partition %d not valid on device %d **\n",
-					part_no, dev_desc->dev);
+					part_no, dev_desc->devnum);
 			return -1;
 		}
 
@@ -1284,7 +1284,7 @@
 		printf("Unknown");
 	}
 
-	printf("\n  Device %d: ", cur_dev->dev);
+	printf("\n  Device %d: ", cur_dev->devnum);
 	dev_print(cur_dev);
 #endif