OFWPCI: Improve resource handling.

• add new rman for prefetchable memory. Is used only if given 'ranges' property contains prefetchable memory range.

• not all ranges in 'ranges' property are subject for rman's filling. Tegra for example, have two addition records which are used for 'pci 'register' -> 'assigned-address' -> 'ranges' machinery. Add sc_ranges_mask for masking not rman related ranges.

• consistently pass unknown (not managed at this level) resources allocation/release/adjust requests to parent.

MFC after: 3 weeks