mtd: introduce mtd_lock_user_prot_reg interface

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/mtdpart.c

@@ -229,7 +229,7 @@ static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
 		size_t len)
 {
 	struct mtd_part *part = PART(mtd);
-	return part->master->lock_user_prot_reg(part->master, from, len);
+	return mtd_lock_user_prot_reg(part->master, from, len);
 }
 
 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,