P2020 integrated 3 PCIe controllers, which is compatible with
the PCI Express™ Base Specification, Revision 1.0a, and this
patch is to add DT node for each PCIe controller.
Signed-off-by: NHou Zhiqiang <Zhiqiang.Hou@nxp.com>
Reviewed-by: NBin Meng <bmeng.cn@gmail.com>
Reviewed-by: NPrabhakar Kushwaha <prabhakar.kushwaha@nxp.com>