[PATCH 1/2] powerpc: Make isa_mem_base common to 32 and 64 bits

[Benjamin Herrenschmidt]

> > +/* ISA Memory physical address (or 0 if none) */
>                                    ^^^^^^^^^^^^
> > +resource_size_t isa_mem_base    = 0;
> 
> Let's hope this doesn't confuse too many people, as 0 is the valid value on
> legacy PC hardware ;-)

True, but that's been our default so far so I'm just not changing
existing behaviour. If it's bogus, it will need a separate fix.

Cheers,
Ben.