Merge branch 'pci/rockchip'

- Make 'ep-gpios' DT property optional (Chen-Yu Tsai)

- Add FriendlyARM NanoPi M4B to rockchip DT binding (Chen-Yu Tsai)

* pci/rockchip:
  dt-bindings: arm: rockchip: Add FriendlyARM NanoPi M4B
  PCI: rockchip: Make 'ep-gpios' DT property optional