mtd: return badblockbits back

In commit c7b28e2 the initialization of
the backblockbits was accidentally removed. This patch returns it back,
because otherwise some NAND drivers are broken.

This problem was reported by "Saxena, Parth <parth.saxena@ti.com>" here:
http://lists.infradead.org/pipermail/linux-mtd/2011-April/035221.html

Reported-by: Saxena, Parth <parth.saxena@ti.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Tested-by: Saxena, Parth <parth.saxena@ti.com>
Acked-by: Saxena, Parth <parth.saxena@ti.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Cc: stable@kernel.org [2.6.36+]
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/nand/nand_base.c

@@ -3106,6 +3106,8 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
 		chip->chip_shift += 32 - 1;
 	}
 
+	chip->badblockbits = 8;
+
 	/* Set the bad block position */
 	if (mtd->writesize > 512 || (busw & NAND_BUSWIDTH_16))
 		chip->badblockpos = NAND_LARGE_BADBLOCK_POS;