A new "arm32_dma_range" structure now describes a DMA window, with
a system address base, bus address base, and length. In addition to
providing info about which memory regions are legal for DMA, the new
structure provides address translation support, as well.
As before, if a tag does not list any ranges, then all addresses are
considered valid, and no DMA address translation is performed.
This allows us to remove a large chunk of code which was duplicated and
tweaked slightly (to do the address translation) from the stock ARM
bus_dma in the XScale IOP and ARM Integrator ports.
Test compiled on all ARM platforms, test booted on Intel IQ80321 and Shark.