dt-bindings: gpio: Add bindings for Toshiba Visconti GPIO Controller

Add bindings for the Toshiba Visconti GPIO Controller.
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Punit Agrawal <punit1.agrawal@toshiba.co.jp>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

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

+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/gpio/toshiba,gpio-visconti.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Toshiba Visconti ARM SoCs GPIO controller
+
+maintainers:
+  - Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
+
+properties:
+  compatible:
+    items:
+      - const: toshiba,gpio-tmpv7708
+
+  reg:
+    maxItems: 1
+
+  "#gpio-cells":
+    const: 2
+
+  gpio-ranges: true
+
+  gpio-controller: true
+
+  interrupt-controller: true
+
+  "#interrupt-cells":
+    const: 2
+
+  interrupts:
+    description:
+      interrupt mapping one per GPIO.
+    minItems: 16
+    maxItems: 16
+
+required:
+  - compatible
+  - reg
+  - "#gpio-cells"
+  - gpio-ranges
+  - gpio-controller
+  - interrupt-controller
+  - "#interrupt-cells"
+  - interrupt-parent
+
+additionalProperties: false
+
+examples:
+  - |
+      #include <dt-bindings/interrupt-controller/irq.h>
+      #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+      soc {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        gpio: gpio@28020000 {
+          compatible = "toshiba,gpio-tmpv7708";
+          reg = <0 0x28020000 0 0x1000>;
+          #gpio-cells = <0x2>;
+          gpio-ranges = <&pmux 0 0 32>;
+          gpio-controller;
+          interrupt-controller;
+          #interrupt-cells = <2>;
+          interrupt-parent = <&gic>;
+        };
+      };
+...