[patch] ppc64 native target for gcc

[Eric Christopher]

>
> Actually, I was thinking about this.  If you point CC=gcc64, then,  
> config.guess should return powerpc64.  If you point it at a 32-bit  
> default, config.guess can return powerpc.  I think this would be  
> safe, as very, very few people will have a 64 bit default compiler,  
> and those that do, want the next one to be as well.

Well, right now we use uname -p to get the machine type. We'd have to  
use a different method in place. Not that it's a bad idea though.

-eric