powerpc/p2041rdb: add NAND and NAND boot support

New P2041RDB board will add a NAND chip, so add support for NAND and
NAND boot.

Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>
2 files changed