dt-bindings: hwmon: as370: convert to dtschema

Convert existing binding to support validation.

This is a straightforward conversion with now new properties.

Reviewed-by: Rob Herring <[e-mail]>
Signed-off-by: Javier Carrasco <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Guenter Roeck <[e-mail]>

Documentation/devicetree/bindings/hwmon/as370.txt

···
-Bindings for Synaptics AS370 PVT sensors
-
-Required properties:
-- compatible : "syna,as370-hwmon"
-- reg        : address and length of the register set.
-
-Example:
-	hwmon@ea0810 {
-		compatible = "syna,as370-hwmon";
-		reg = <0xea0810 0xc>;
-	};

Documentation/devicetree/bindings/hwmon/syna,as370.yaml

···
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwmon/syna,as370.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Synaptics AS370 PVT sensors
+
+maintainers:
+  - Javier Carrasco <[e-mail]>
+
+properties:
+  compatible:
+    const: syna,as370-hwmon
+
+  reg:
+    description:
+      Address and length of the register set.
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    sensor@ea0810 {
+        compatible = "syna,as370-hwmon";
+        reg = <0xea0810 0xc>;
+    };