PPC4xx: Add support for Korat PPC440EPx board to "for-1.3.2" branch

Hi Stefan,

Here are my patches to add support for the Korat board to the "for-1.3.2" branch of the U-Boot PPC44x repository. They should be essentially the same as the ones I submitted previously; I haven't tried anything with FDT support yet.

Best regards,
Larry