In xgene_pcie_map_bus(), we neglected to add in the register offset when
calculating the config space address.  This means all config accesses
operated on the first four bytes of config space.

Add the register offset to the config space base address.

Also correct the xgene_pcie_map_bus() prototype to fix a compiler warning.

[bhelgaas: changelog]
Fixes: 350f8be5 ("PCI: xgene: Convert to use generic config accessors")
Posting: http://lkml.kernel.org/r/1424214840-26498-1-git-send-email-fkan@apm.comSigned-off-by: NFeng Kan <fkan@apm.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NTanmay Inamdar <tinamdar@apm.com>
Acked-by: NRob Herring <robh@kernel.org>