[POWERPC] Disable PCI IO/Mem on a device when resources can't be allocated

[POWERPC] Disable PCI IO/Mem on a device when resources can't be allocated

This patch changes the PowerPC PCI code to disable IO and/or Memory
decoding on a PCI device when a resource of that type failed to be
allocated.  This is done to avoid having unallocated dangling BARs
enabled that might try to decode on top of other devices.

If a proper resource is assigned later on, then pci_enable_device()
will take care of re-enabling decoding.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>