dt-bindings:iio:light:avago,apds9960: txt to yaml conversion

Very simple binding that we could move into trivial-devices.yaml
with a small loss of documentation.
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Matt Ranostay <matt.ranostay@konsulko.com>
Link: https://lore.kernel.org/r/20201031184854.745828-15-jic23@kernel.org

Documentation/devicetree/bindings/iio/light/apds9960.txt

-* Avago APDS9960 gesture/RGB/ALS/proximity sensor
-
-https://www.avagotech.com/docs/AV02-4191EN
-
-Required properties:
-
-  - compatible: must be "avago,apds9960"
-  - reg: the I2c address of the sensor
-  - interrupts : the sole interrupt generated by the device
-
-  Refer to interrupt-controller/interrupts.txt for generic interrupt client
-  node bindings.
-
-Example:
-
-apds9960@39 {
-	compatible = "avago,apds9960";
-	reg = <0x39>;
-	interrupt-parent = <&gpio1>;
-	interrupts = <16 1>;
-};

Documentation/devicetree/bindings/iio/light/avago,apds9960.yaml

+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/light/avago,apds9960.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Avago APDS9960 gesture/RGB/ALS/proximity sensor
+
+maintainers:
+  - Matt Ranostay <matt.ranostay@konsulko.com>
+
+description: |
+  Datasheet at https://www.avagotech.com/docs/AV02-4191EN
+
+properties:
+  compatible:
+    const: avago,apds9960
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+additionalProperties: false
+
+required:
+  - compatible
+  - reg
+
+examples:
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        light-sensor@39 {
+            compatible = "avago,apds9960";
+            reg = <0x39>;
+            interrupt-parent = <&gpio1>;
+            interrupts = <16 1>;
+        };
+    };
+...