dt-bindings: watchdog: convert Broadcom's WDT to the json-schema

This helps validating DTS files.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211115055354.6089-1-zajec5@gmail.comSigned-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

Documentation/devicetree/bindings/watchdog/brcm,bcm7038-wdt.txt

-BCM7038 Watchdog timer
-
-Required properties:
-
-- compatible : should be "brcm,bcm7038-wdt"
-- reg : Specifies base physical address and size of the registers.
-
-Optional properties:
-
-- clocks: The clock running the watchdog. If no clock is found the
-	  driver will default to 27000000 Hz.
-
-Example:
-
-watchdog@f040a7e8 {
-	compatible = "brcm,bcm7038-wdt";
-	clocks = <&upg_fixed>;
-	reg = <0xf040a7e8 0x16>;
-};

Documentation/devicetree/bindings/watchdog/brcm,bcm7038-wdt.yaml

+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/watchdog/brcm,bcm7038-wdt.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: BCM7038 watchdog timer
+
+allOf:
+  - $ref: "watchdog.yaml#"
+
+maintainers:
+  - Florian Fainelli <f.fainelli@gmail.com>
+  - Justin Chen <justinpopo6@gmail.com>
+  - Rafał Miłecki <rafal@milecki.pl>
+
+properties:
+  compatible:
+    const: brcm,bcm7038-wdt
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+    description: >
+      The clock running the watchdog. If no clock is found the driver will
+      default to 27000000 Hz.
+
+unevaluatedProperties: false
+
+required:
+  - reg
+
+examples:
+  - |
+    watchdog@f040a7e8 {
+      compatible = "brcm,bcm7038-wdt";
+      reg = <0xf040a7e8 0x16>;
+      clocks = <&upg_fixed>;
+    };