[SPARC64]: Handle PCI bridges without 'ranges' property.

This fixes the IDE controller not showing up on Netra-T1
systems.

Just like Simba bridges, some PCI bridges can lack the
'ranges' OBP property.  So we handle this similarly to
the existing Simba code:

1) In of_device register address resolving, we push the
   translation to the parent.

2) In PCI device scanning, we interrogate the PCI config
   space registers of the PCI bus device in order to resolve
   the resources, just like the generic Linux PCI probing
   code does.

With much help and testing from Fabio, who also reported
the initial problem.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Fabio Massimo Di Nitto <fabbione@ubuntu.com>