mtd: atmel_nand: Disable subpage NAND write when using Atmel PMECC

Disable subpage write when using PMECC to prevent buggy partial page write.

This fix has been taken from linux sources (see commit
90445ff6241e2a13445310803e2efa606c61f276)

Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Acked-by: Josh Wu <josh.wu@atmel.com>
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>

drivers/mtd/nand/atmel_nand.c

@@ -882,6 +882,7 @@ static int atmel_pmecc_nand_init_params(struct nand_chip *nand,
 		return -ENOMEM;
 	}
 
+	nand->options |= NAND_NO_SUBPAGE_WRITE;
 	nand->ecc.read_page = atmel_nand_pmecc_read_page;
 	nand->ecc.write_page = atmel_nand_pmecc_write_page;
 	nand->ecc.strength = cap;