mtd: nand: Fix probe of Samsung NAND chips

Apparently, the check for a 6-byte ID string introduced by commit
426c457a ("mtd: nand: extend NAND flash
detection to new MLC chips") is NOT sufficient to determine whether or
not a Samsung chip uses their new MLC detection scheme or the old,
standard scheme. This adds a condition to check cell type.
Signed-off-by: NTilman Sauerbeck <tilman@code-monkey.de>
Signed-off-by: NBrian Norris <norris@broadcom.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>
Cc: stable@kernel.org

drivers/mtd/nand/nand_base.c

@@ -2866,6 +2866,7 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
 		 */
 		if (id_data[0] == id_data[6] && id_data[1] == id_data[7] &&
 				id_data[0] == NAND_MFR_SAMSUNG &&
+				(chip->cellinfo & NAND_CI_CELLTYPE_MSK) &&
 				id_data[5] != 0x00) {
 			/* Calc pagesize */
 			mtd->writesize = 2048 << (extid & 0x03);