dw_pcie_host_init() creates the PCI host bridge with pci_common_init_dev(),
an ARM-specific function that supplies the ARM-specific pci_sys_data
structure as the PCI "sysdata".  To use dw_pcie_host_init() on other
architectures, we will copy the internals of pci_common_init_dev() into
pcie-designware.c instead of calling it, and dw_pcie_host_init() will
supply the DesignWare pcie_port structure as "sysdata".

Most ARM "sysdata" users are specific to non-DesignWare host bridges;
they'll be unaffected because those bridges will continue to have the ARM
pci_sys_data.  Most of the rest are ARM-generic functions called by
pci_common_init_dev(); these will be unaffected because dw_pcie_host_init()
will no longer call pci_common_init().

But the ARM pcibios_align_resource() can be called by the PCI core for any
bridge, so it can't depend on sysdata since it may be either pci_sys_data
or pcie_port.

Remove the pcibios_align_resource() dependency on sysdata by replacing the
pci_sys_data->align_resource pointer with a global function pointer.

This is less general (we can no longer have per-host bridge
align_resource() methods), but the pci_sys_data->align_resource pointer was
used only by Marvell (see mvebu_pcie_enable()), so this would only be a
problem if we had a system with a combination of Marvell and other host
bridges

[bhelgaas: changelog]
Signed-off-by: Gabriele Paoloni <gabriele.paoloni@huawei.com>
Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Pratyush Anand <pratyush.anand@gmail.com>