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

This reverts commit 553aa765 at Ben H's
request, because it confused IORESOURCE_* flags with command register
bits.

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