dt-bindings: rng: atmel,at91-trng: convert Atmel TRNG to dtschema

Convert the Atmel TRNG bindings to DT schema.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211227183251.132525-2-krzysztof.kozlowski@canonical.com

Documentation/devicetree/bindings/rng/atmel,at91-trng.yaml

+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/rng/atmel,at91-trng.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Atmel AT91 True Random Number Generator
+
+maintainers:
+  - Nicolas Ferre <nicolas.ferre@microchip.com>
+  - Alexandre Belloni <alexandre.belloni@bootlin.com>
+  - Ludovic Desroches <ludovic.desroches@microchip.com>
+
+properties:
+  compatible:
+    enum:
+      - atmel,at91sam9g45-trng
+      - microchip,sam9x60-trng
+
+  clocks:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - clocks
+  - interrupts
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    rng@fffcc000 {
+        compatible = "atmel,at91sam9g45-trng";
+        reg = <0xfffcc000 0x4000>;
+        interrupts = <6 IRQ_TYPE_LEVEL_HIGH 0>;
+        clocks = <&trng_clk>;
+    };

Documentation/devicetree/bindings/rng/atmel-trng.txt

-Atmel TRNG (True Random Number Generator) block
-
-Required properties:
-- compatible : Should be "atmel,at91sam9g45-trng" or "microchip,sam9x60-trng"
-- reg : Offset and length of the register set of this block
-- interrupts : the interrupt number for the TRNG block
-- clocks: should contain the TRNG clk source
-
-Example:
-
-trng@fffcc000 {
-	compatible = "atmel,at91sam9g45-trng";
-	reg = <0xfffcc000 0x4000>;
-	interrupts = <6 IRQ_TYPE_LEVEL_HIGH 0>;
-	clocks = <&trng_clk>;
-};