davinci: DA850/OMAP-L138 EVM expander setup and UI card detection

DA850/OMAP-L138 EVM can be connected to an UI card which has various
peripherals on it.The UI card has TCA6416 expander which can be probed
to check whether the UI card is connected or not. If the UI card is
connected, setup NOR and NAND devices. This is done via the expander
setup callback.

Signed-off-by: Chaithrika U S <chaithrika@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>