dt-bindings: reset: snps,axs10x-reset: Convert to yaml

Convert the device tree bindings for the AXS10x reset controller to YAML
schema to allow participating in DT validation.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220407154338.4190674-8-p.zabel@pengutronix.de

Documentation/devicetree/bindings/reset/snps,axs10x-reset.txt

-Binding for the AXS10x reset controller
-
-This binding describes the ARC AXS10x boards custom IP-block which allows
-to control reset signals of selected peripherals. For example DW GMAC, etc...
-This block is controlled via memory-mapped register (AKA CREG) which
-represents up-to 32 reset lines.
-
-As of today only the following lines are used:
- - DW GMAC - line 5
-
-This binding uses the common reset binding[1].
-
-[1] Documentation/devicetree/bindings/reset/reset.txt
-
-Required properties:
-- compatible: should be "snps,axs10x-reset".
-- reg: should always contain pair address - length: for creg reset
-  bits register.
-- #reset-cells: from common reset binding; Should always be set to 1.
-
-Example:
-	reset: reset-controller@11220 {
-		compatible = "snps,axs10x-reset";
-		#reset-cells = <1>;
-		reg = <0x11220 0x4>;
-	};
-
-Specifying reset lines connected to IP modules:
-	ethernet@.... {
-		....
-		resets = <&reset 5>;
-		....
-	};

Documentation/devicetree/bindings/reset/snps,axs10x-reset.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/reset/snps,axs10x-reset.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: AXS10x reset controller
+
+maintainers:
+  - Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
+
+description: |
+  This binding describes the ARC AXS10x boards custom IP-block which allows
+  to control reset signals of selected peripherals. For example DW GMAC, etc...
+  This block is controlled via memory-mapped register (AKA CREG) which
+  represents up-to 32 reset lines.
+  As of today only the following lines are used:
+   - DW GMAC - line 5
+
+properties:
+  compatible:
+    const: snps,axs10x-reset
+
+  reg:
+    maxItems: 1
+
+  '#reset-cells':
+    const: 1
+
+required:
+  - compatible
+  - reg
+  - '#reset-cells'
+
+additionalProperties: false
+
+examples:
+  - |
+    reset: reset-controller@11220 {
+        compatible = "snps,axs10x-reset";
+        #reset-cells = <1>;
+        reg = <0x11220 0x4>;
+    };
+
+    // Specifying reset lines connected to IP modules:
+    ethernet {
+        resets = <&reset 5>;
+    };