Merge tag 'hi6620-dt-for-4.2' of git://github.com/hisilicon/linux-hisi into next/dt

ARM64: DT: Hisilicon hi6220 soc and hikey board updates for 4.2

- Added the devicetree bindings document for hi6220 SoC
- Added the devicetree bindings document for hi6220 clock
- Added dts files for hi6220 SoC and hikey board

* tag 'hi6620-dt-for-4.2' of git://github.com/hisilicon/linux-hisi:
  arm64: dts: Add dts files for Hisilicon Hi6220 SoC
  clk: hi6220: Document devicetree bindings for hi6220 clock
  arm64: hi6220: Document devicetree bindings for Hisilicon hi6220 SoC