PCI: layerscape: Add LX2160A rev2 EP mode support

The LX2160A rev2 uses the same PCIe IP as LS2088A, but LX2160A rev2 PCIe
controller is integrated with different stride between PFs' register
address.

Link: https://lore.kernel.org/r/20201026051448.1913-2-Zhiqiang.Hou@nxp.com


Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>