dt-bindings:iio:adc:st,stmpe-adc yaml conversion

Conversion from freeform text to yaml.
One oddity in this binding is that, for historical reasons it requires
the node name to be stmpe_adc.  I've put that in the decription field
but I'm not sure if there is a better way to specify this?
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: Stefan Agner <stefan@agner.ch>
Link: https://lore.kernel.org/r/20200909175946.395313-4-jic23@kernel.org

Documentation/devicetree/bindings/iio/adc/st,stmpe-adc.yaml

+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/st,stmpe-adc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ADC on an STMPE multifunction device.
+
+maintainers:
+  - Stefan Agner <stefan@agner.ch>
+
+description:
+  This ADC forms part of an ST microelectronics STMPE multifunction device .
+  The ADC is shared with the STMPE touchscreen. As a result some ADC related
+  settings are specified in the parent node.
+  The node name myst be stmpe_adc and should be a child node of the stmpe node
+  to which it belongs.
+
+properties:
+  compatible:
+    const: st,stmpe-adc
+
+  st,norequest-mask:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      Bitmask specifying which ADC channels should _not_ be
+      requestable due to different usage (e.g. touch).
+
+  "#io-channel-cells":
+    const: 1
+
+required:
+  - compatible
+
+additionalProperties: false
+
+examples:
+  - |
+    stmpe {
+        stmpe_adc {
+            compatible = "st,stmpe-adc";
+            st,norequest-mask = <0x0F>; /* dont use ADC CH3-0 */
+        };
+    };
+...

Documentation/devicetree/bindings/iio/adc/stmpe-adc.txt

-STMPE ADC driver
-----------------
-
-Required properties:
- - compatible: "st,stmpe-adc"
-
-Optional properties:
-Note that the ADC is shared with the STMPE touchscreen. ADC related settings
-have to be done in the mfd.
-- st,norequest-mask: bitmask specifying which ADC channels should _not_ be
-  requestable due to different usage (e.g. touch)
-
-Node name must be stmpe_adc and should be child node of stmpe node to
-which it belongs.
-
-Example:
-
-	stmpe_adc {
-		compatible = "st,stmpe-adc";
-		st,norequest-mask = <0x0F>; /* dont use ADC CH3-0 */
-	};