dt-bindings: pwm: mtk-disp: add MT8167 SoC binding

Add binding for MT8167 SoC. The IP is compatible with MT8173.
Signed-off-by: Fabien Parent <fparent@baylibre.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Documentation/devicetree/bindings/pwm/pwm-mtk-disp.txt

@@ -4,6 +4,7 @@ Required properties:
  - compatible: should be "mediatek,<name>-disp-pwm":
    - "mediatek,mt2701-disp-pwm": found on mt2701 SoC.
    - "mediatek,mt6595-disp-pwm": found on mt6595 SoC.
+   - "mediatek,mt8167-disp-pwm", "mediatek,mt8173-disp-pwm": found on mt8167 SoC.
    - "mediatek,mt8173-disp-pwm": found on mt8173 SoC.
  - reg: physical base address and length of the controller's registers.
  - #pwm-cells: must be 2. See pwm.yaml in this directory for a description of