dt-bindings: interrupt-controller: Convert opencores,or1k-pic to DT schema

Convert the OpenRISC PIC interrupt controller binding to schema
format. It's a straight-forward conversion of the typical interrupt
controller.

Signed-off-by: Rob Herring (Arm) <[e-mail]>
Signed-off-by: Stafford Horne <[e-mail]>

Documentation/devicetree/bindings/interrupt-controller/opencores,or1k-pic.txt

···
-OpenRISC 1000 Programmable Interrupt Controller
-
-Required properties:
-
-- compatible : should be "opencores,or1k-pic-level" for variants with
-  level triggered interrupt lines, "opencores,or1k-pic-edge" for variants with
-  edge triggered interrupt lines or "opencores,or1200-pic" for machines
-  with the non-spec compliant or1200 type implementation.
-
-  "opencores,or1k-pic" is also provided as an alias to "opencores,or1200-pic",
-  but this is only for backwards compatibility.
-
-- interrupt-controller : Identifies the node as an interrupt controller
-- #interrupt-cells : Specifies the number of cells needed to encode an
-  interrupt source. The value shall be 1.
-
-Example:
-
-intc: interrupt-controller {
-	compatible = "opencores,or1k-pic-level";
-	interrupt-controller;
-	#interrupt-cells = <1>;
-};

Documentation/devicetree/bindings/interrupt-controller/opencores,or1k-pic.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/interrupt-controller/opencores,or1k-pic.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: OpenRISC 1000 Programmable Interrupt Controller
+
+maintainers:
+  - Stefan Kristiansson <[e-mail]>
+
+properties:
+  compatible:
+    enum:
+      - opencores,or1k-pic-level
+      - opencores,or1k-pic-edge
+      - opencores,or1200-pic
+      - opencores,or1k-pic
+
+  interrupt-controller: true
+
+  '#interrupt-cells':
+    const: 1
+
+required:
+  - compatible
+  - interrupt-controller
+  - '#interrupt-cells'
+
+additionalProperties: false
+
+examples:
+  - |
+    interrupt-controller {
+        compatible = "opencores,or1k-pic-level";
+        interrupt-controller;
+        #interrupt-cells = <1>;
+    };