[PATCH] implement AT_PLATFORM for powerpc

[Paul Mackerras]

Kumar Gala writes:

> We should probably add two new AT_PLATFORM: "ppc8548" and "ppc5554".  
> "ppc8548" should be used for e500v2, and "ppc5554" for "e200z6".

How different are they in user-level ISA or in instruction scheduling
requirements?

> You aren't seeting PPC_FEATURE_BOOKE for anything.  We need to be a little 
> careful since 'isel' isn't implemented in the very first 440's.

Oops, I must have sent the wrong version of the patch.  Do we know
which 440s have or don't have isel?

Paul.