[POWERPC] DTS cleanup

Removed the following cruft from .dts files:
* 32-bit in cpu node -- doesn't exist in any spec and not used by kernel
* removed built-in (chrp legacy)
* Removed #interrupt-cells in places they don't need to be set
* Fixed ranges on lite5200*
* Removed clock-frequency from i8259 pic node, not sure where this came from
* Removed big-endian from i8259 pic nodes, this was just bogus

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