[MTD] OneNAND: Check first or second pages for bad block information

OneNAND records bad block information in the out-of-band area of either the first or second page of a block.  Due to a logic error, only the first page was being checked.
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>

drivers/mtd/onenand/onenand_bbt.c

@@ -68,7 +68,7 @@ static int create_bbt(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
 
 	printk(KERN_INFO "Scanning device for bad blocks\n");
 
-	len = 1;
+	len = 2;
 
 	/* We need only read few bytes from the OOB area */
 	scanlen = ooblen = 0;