mtd: do not use mtd->block_markbad directly

Instead, use the new 'mtd_can_have_bb()', or just rely on 'mtd_block_markbad()'
return code, which will be -EOPNOTSUPP if bad blocks are not supported.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c
index fbf3cb1..1ed5103 100644
--- a/drivers/mtd/mtdconcat.c
+++ b/drivers/mtd/mtdconcat.c
@@ -673,7 +673,7 @@
 	struct mtd_concat *concat = CONCAT(mtd);
 	int i, err = -EINVAL;
 
-	if (!concat->subdev[0]->block_markbad)
+	if (!mtd_can_have_bb(concat->subdev[0]))
 		return 0;
 
 	if (ofs > mtd->size)