powerpc/44x: Update Canyonlands defconfig to support NOR, NAND and RTC

This patch adds support for the following devices to the Canyonlands
defconfig file:
- NOR FLASH
- PPC4xx NAND controller (NDFC)
- I2C RTC (M41T80)
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>