Enable NAND boot support using SPL framework. To boot from
NAND, either use DIP switches on board, or "qixis_reset nand"
command. Details of forming NAND image can be found in README.
Signed-off-by: Scott Wood <scottwood@freescale.com>
[York Sun: Remove +S from defconfig after commit 252ed872]
Signed-off-by: York Sun <yorksun@freescale.com>
