mtd: zero out mtd_partition struct before using it

It's easier to guarantee we've cleared out all unused fields with
memset() than by manually initializing each field.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>

drivers/mtd/mtdpart.c

@@ -596,11 +596,10 @@ int mtd_add_partition(struct mtd_info *master, const char *name,
 	if (length <= 0)
 		return -EINVAL;
 
+	memset(&part, 0, sizeof(part));
 	part.name = name;
 	part.size = length;
 	part.offset = offset;
-	part.mask_flags = 0;
-	part.ecclayout = NULL;
 
 	new = allocate_partition(master, &part, -1, offset);
 	if (IS_ERR(new))