dt-bindings: arm: Convert Marvell MMP board/soc bindings to json-schema

Convert Marvell MMP SoC bindings to DT schema format using json-schema.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Reviewed-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/arm/mrvl/mrvl.txt

-Marvell Platforms Device Tree Bindings
-----------------------------------------------------
-
-PXA168 Aspenite Board
-Required root node properties:
-	- compatible = "mrvl,pxa168-aspenite", "mrvl,pxa168";
-
-PXA910 DKB Board
-Required root node properties:
-	- compatible = "mrvl,pxa910-dkb";
-
-MMP2 Brownstone Board
-Required root node properties:
-	- compatible = "mrvl,mmp2-brownstone", "mrvl,mmp2";

Documentation/devicetree/bindings/arm/mrvl/mrvl.yaml

+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/arm/mrvl/mrvl.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Marvell Platforms Device Tree Bindings
+
+maintainers:
+  - Lubomir Rintel <lkundrak@v3.sk>
+
+properties:
+  $nodename:
+    const: '/'
+  compatible:
+    oneOf:
+      - description: PXA168 Aspenite Board
+        items:
+          - enum:
+              - mrvl,pxa168-aspenite
+          - const: mrvl,pxa168
+      - description: PXA910 DKB Board
+        items:
+          - enum:
+              - mrvl,pxa910-dkb
+          - const: mrvl,pxa910
+      - description: MMP2 based boards
+        items:
+          - enum:
+              - mrvl,mmp2-brownstone
+          - const: mrvl,mmp2
+...