dt-bindings: pinctrl: uniphier: Add child node definitions to describe pin mux and configuration

In arch/arm/boot/dts/uniphier-pinctrl.dtsi, there are child nodes of
pinctrl that defines pinmux and pincfg, however, there are no rules about
that in dt-bindings.

'make dtbs_check' results an error with the following message:

   pinctrl: 'ain1', 'ain2', 'ainiec1', 'aout', 'aout1', 'aout2', ...
   ... 'usb2', 'usb3' do not match any of the regexes: 'pinctrl-[0-9]+'

To avoid the issue, add the rules of pinmux and pincfg in each child node
and grandchild node.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/1636416699-21033-1-git-send-email-hayashi.kunihiko@socionext.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Documentation/devicetree/bindings/pinctrl/socionext,uniphier-pinctrl.yaml

@@ -26,11 +26,45 @@ properties:
       - socionext,uniphier-pxs3-pinctrl
       - socionext,uniphier-nx1-pinctrl
 
+additionalProperties:
+  type: object
+
+  allOf:
+    - $ref: pincfg-node.yaml#
+    - $ref: pinmux-node.yaml#
+
+  properties:
+    phandle: true
+    function: true
+    groups: true
+    pins: true
+    bias-pull-up: true
+    bias-pull-down: true
+    bias-pull-pin-default: true
+    drive-strength: true
+
+  additionalProperties:
+    type: object
+
+    allOf:
+      - $ref: pincfg-node.yaml#
+      - $ref: pinmux-node.yaml#
+
+    properties:
+      phandle: true
+      function: true
+      groups: true
+      pins: true
+      bias-pull-up: true
+      bias-pull-down: true
+      bias-pull-pin-default: true
+      drive-strength: true
+
+    unevaluatedProperties: false
+
 required:
   - compatible
 
-additionalProperties: false
-
 examples:
   - |
     // The UniPhier pinctrl should be a subnode of a "syscon" compatible node.