Cleanup PPC40x eval boards (bubinga, walnut and sycamore) to support U-Boot
as bootloader.  The OpenBIOS bd_info struct is not used in the kernel
anymore (only U-Boot now).

uImage (U-Boot) tested on walnut, sycamore and bubinga
zImage (OpenBIOS) tested on sycamore, bubinga and ebony
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Matt Porter <mporter@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>