versatile_pci: Implement the PCI controller's control registers
The versatile_pci PCI controller has a set of control registers which
handle the mapping between PCI and system address spaces. Implement
these registers (though for now they have no effect since we don't
implement mapping PCI space into system memory at all).
The most natural order for our sysbus regions has the control
registers at the start, so move all the others down one.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Paul Brook <paul@codesourcery.com>