powerpc/83xx: add NAND support for the MPC8360E-RDK boards

The StMicro NAND chip (512Mbit, 64MB) is connected to the local bus,
the first local bus' user-programmable machine is configured by the
firmware to work with NAND chips.

QE GPIO pin is used to poll the NAND's Ready-Not-Busy signal.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>