dt-bindings: firmware: Convert cznic,turris-mox-rwtm to DT schema

Convert the CZ.NIC Turris Mox rWTM firmware binding to DT schema format.
Add the "marvell,armada-3700-rwtm-firmware" compatible which was not
documented.

Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Rob Herring (Arm) <[e-mail]>

Documentation/devicetree/bindings/firmware/cznic,turris-mox-rwtm.txt

···
-Turris Mox rWTM firmware driver
-
-Required properties:
- - compatible		: Should be "cznic,turris-mox-rwtm"
- - mboxes		: Must contain a reference to associated mailbox
-
-This device tree node should be used on Turris Mox, or potentially another A3700
-compatible device running the Mox's rWTM firmware in the secure processor (for
-example it is possible to flash this firmware into EspressoBin).
-
-Example:
-
-	firmware {
-		turris-mox-rwtm {
-			compatible = "cznic,turris-mox-rwtm";
-			mboxes = <&rwtm 0>;
-			status = "okay";
-		};
-	};

Documentation/devicetree/bindings/firmware/cznic,turris-mox-rwtm.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/firmware/cznic,turris-mox-rwtm.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: CZ.NIC Turris Mox rWTM firmware
+
+maintainers:
+  - Marek Behún <[e-mail]>
+
+description:
+  This device tree node should be used on Turris Mox, or potentially another
+  A3700 compatible device running the Mox's rWTM firmware in the secure
+  processor (for example it is possible to flash this firmware into
+  EspressoBin).
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - const: marvell,armada-3700-rwtm-firmware
+          - const: cznic,turris-mox-rwtm
+      - const: marvell,armada-3700-rwtm-firmware
+
+  mboxes:
+    maxItems: 1
+
+required:
+  - compatible
+  - mboxes
+
+additionalProperties: false
+
+examples:
+  - |
+    turris-mox-rwtm {
+        compatible = "marvell,armada-3700-rwtm-firmware", "cznic,turris-mox-rwtm";
+        mboxes = <&rwtm 0>;
+    };

MAINTAINERS

···
 F:	Documentation/ABI/testing/sysfs-bus-moxtet-devices
 F:	Documentation/ABI/testing/sysfs-firmware-turris-mox-rwtm
 F:	Documentation/devicetree/bindings/bus/cznic,moxtet.yaml
-F:	Documentation/devicetree/bindings/firmware/cznic,turris-mox-rwtm.txt
+F:	Documentation/devicetree/bindings/firmware/cznic,turris-mox-rwtm.yaml
 F:	Documentation/devicetree/bindings/firmware/cznic,turris-omnia-mcu.yaml
 F:	Documentation/devicetree/bindings/interrupt-controller/marvell,mpic.yaml
 F:	Documentation/devicetree/bindings/leds/cznic,turris-omnia-leds.yaml