mtd: docg3: use mtd_set_ecclayout() where appropriate

Use the mtd_set_ecclayout() helper instead of directly assigning the
mtd->ecclayout field.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c
index e7b2e43..6b516e1 100644
--- a/drivers/mtd/devices/docg3.c
+++ b/drivers/mtd/devices/docg3.c
@@ -1857,7 +1857,7 @@
 	mtd->_read_oob = doc_read_oob;
 	mtd->_write_oob = doc_write_oob;
 	mtd->_block_isbad = doc_block_isbad;
-	mtd->ecclayout = &docg3_oobinfo;
+	mtd_set_ecclayout(mtd, &docg3_oobinfo);
 	mtd->oobavail = 8;
 	mtd->ecc_strength = DOC_ECC_BCH_T;