Merge branch 'clk-ralink' into clk-next

Merge branch 'clk-ralink' into clk-next

 - Proper clk driver for Mediatek MT7621 SoCs

* clk-ralink:
  MAINTAINERS: add MT7621 CLOCK maintainer
  staging: mt7621-dts: use valid vendor 'mediatek' instead of invalid 'mtk'
  staging: mt7621-dts: make use of new 'mt7621-clk'
  clk: ralink: add clock driver for mt7621 SoC
  dt: bindings: add mt7621-sysc device tree binding documentation
  dt-bindings: clock: add dt binding header for mt7621 clocks