In r350842 I've switched the bus pass to resource so it matches the other
clock drivers but this cannot work as this drivers is meant to match
the dts node '/clocks' and if we don't do it at this pass simplebus is
catching this node and we cannot attach.
This solve booting on Allwinner boards that are still using /clocks (A20 SoC)
MFC after: 3 days