dt-bindings: phy: brcm,kona-usb2-phy: convert to YAML

Convert Broadcom Kona family USB 2.0 PHY bindings to DT schema.
Signed-off-by: Stanislav Jakubek <stano.jakubek@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230427190725.GA7730@standask-GA-A55M-S2HPSigned-off-by: Vinod Koul <vkoul@kernel.org>

Documentation/devicetree/bindings/phy/brcm,kona-usb2-phy.txt

-BROADCOM KONA USB2 PHY
-
-Required properties:
- - compatible: brcm,kona-usb2-phy
- - reg: offset and length of the PHY registers
- - #phy-cells: must be 0
-Refer to phy/phy-bindings.txt for the generic PHY binding properties
-
-Example:
-
-	usbphy: usb-phy@3f130000 {
-		compatible = "brcm,kona-usb2-phy";
-		reg = <0x3f130000 0x28>;
-		#phy-cells = <0>;
-	};

Documentation/devicetree/bindings/phy/brcm,kona-usb2-phy.yaml

+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/brcm,kona-usb2-phy.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Broadcom Kona family USB 2.0 PHY
+
+maintainers:
+  - Florian Fainelli <f.fainelli@gmail.com>
+
+properties:
+  compatible:
+    const: brcm,kona-usb2-phy
+
+  reg:
+    maxItems: 1
+
+  '#phy-cells':
+    const: 0
+
+required:
+  - compatible
+  - reg
+  - '#phy-cells'
+
+additionalProperties: false
+
+examples:
+  - |
+    usb-phy@3f130000 {
+        compatible = "brcm,kona-usb2-phy";
+        reg = <0x3f130000 0x28>;
+        #phy-cells = <0>;
+    };
+...