Merge branch 'pci/controller/dt'

- Convert Amlogic Meson AXG DWC PCIe SoC controller bindings to dt-schema
  (Neil Armstrong)

- Restructure i.MX schema to extract common properties to be shared by Root
  Complex and Endpoint schema (Richard Zhu)

* pci/controller/dt:
  dt-bindings: imx6q-pcie: Restruct i.MX PCIe schema
  dt-bindings: PCI: convert amlogic,meson-pcie.txt to dt-schema