Use "request_resource()" to properly fix up PCI resource clashes.

Use "request_resource()" to properly fix up PCI resource clashes.

This is made possible by the previous resource allocation ordering
patch.

Now that we run the pre-existing PCI resource discovery _before_
ACPI resources have been added, we should not "insert" the resources
into any existing tree. If they clash with existing resources, we
should re-allocate them (later, when we have the full resource map).