85xx: Add a 36-bit physical configuration for MPC8536DS

We move all IO addressed (CCSR, localbus, PCI) above the 4G boundary
to allow for larger memory sizes.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Wolfgang Denk <wd@denx.de>

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>