ECC selection constants

/* No ECC. Usage is not recommended ! */
#define NAND_ECC_NONE		0
/* Software ECC 3 byte ECC per 256 Byte data */
#define NAND_ECC_SOFT		1
/* Hardware ECC 3 byte ECC per 256 Byte data */
#define NAND_ECC_HW3_256	2
/* Hardware ECC 3 byte ECC per 512 Byte data */
#define NAND_ECC_HW3_512	3
/* Hardware ECC 6 byte ECC per 512 Byte data */
#define NAND_ECC_HW6_512	4
/* Hardware ECC 6 byte ECC per 512 Byte data */
#define NAND_ECC_HW8_512	6