mtd: add mtd_set_ecclayout() helper function

Add an mtd_set_ecclayout() helper function to avoid direct accesses to the
mtd->ecclayout field. This will ease future reworks of ECC layout
definition.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

include/linux/mtd/mtd.h

@@ -286,6 +286,12 @@ int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,
 int mtd_ooblayout_count_freebytes(struct mtd_info *mtd);
 int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd);
 
+static inline void mtd_set_ecclayout(struct mtd_info *mtd,
+				     struct nand_ecclayout *ecclayout)
+{
+	mtd->ecclayout = ecclayout;
+}
+
 static inline void mtd_set_of_node(struct mtd_info *mtd,
 				   struct device_node *np)
 {