dt-bindings: pwm: Add bindings for Toshiba Visconti PWM Controller

Add bindings for the Toshiba Visconti PWM Controller.
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Documentation/devicetree/bindings/pwm/toshiba,pwm-visconti.yaml

+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pwm/toshiba,pwm-visconti.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Toshiba Visconti PWM Controller
+
+maintainers:
+  - Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
+
+properties:
+  compatible:
+    items:
+      - const: toshiba,visconti-pwm
+
+  reg:
+    maxItems: 1
+
+  '#pwm-cells':
+    const: 2
+
+required:
+  - compatible
+  - reg
+  - '#pwm-cells'
+
+additionalProperties: false
+
+examples:
+  - |
+    soc {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        pwm: pwm@241c0000 {
+            compatible = "toshiba,visconti-pwm";
+            reg = <0 0x241c0000 0 0x1000>;
+            pinctrl-names = "default";
+            pinctrl-0 = <&pwm_mux>;
+            #pwm-cells = <2>;
+        };
+    };