dt-bindings: pwm: renesas,tpu-pwm: Improve json-schema

- Include the general PWM controller schema,
  - Make clocks, power-domains, and resets properties required.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lore.kernel.org/r/d36e3690ce8c5a1e53d054552e4fd8b90d6a5478.1620648868.git.geert+renesas@glider.be
Signed-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/pwm/renesas,tpu-pwm.yaml

@@ -58,6 +58,23 @@ required:
   - compatible
   - reg
   - '#pwm-cells'
+  - clocks
+  - power-domains
+
+allOf:
+  - $ref: pwm.yaml#
+
+  - if:
+      not:
+        properties:
+          compatible:
+            contains:
+              enum:
+                - renesas,tpu-r8a73a4
+                - renesas,tpu-r8a7740
+    then:
+      required:
+        - resets
 
 additionalProperties: false