The software ECC algorithm is not necessary when hardware ECC
is available and can be left out for a smaller image size.
Enable with CONFIG_MTD_ECC_SOFT.

Signed-off-by: Christian Hitz <christian.hitz@aizo.com>
Cc: Scott Wood <scottwood@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>