dt-bindings: net: add schema for Microchip/SMSC LAN95xx USB Ethernet controllers

Create initial schema for Microchip/SMSC LAN95xx USB Ethernet controllers and
import some of currently supported USB IDs form drivers/net/usb/smsc95xx.c

These devices are already used in some of DTs. So, this schema makes it official.
NOTE: there was no previously documented txt based DT binding for this
controllers.
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220517111505.929722-3-o.rempel@pengutronix.de

Documentation/devicetree/bindings/net/microchip,lan95xx.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/microchip,lan95xx.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: The device tree bindings for the USB Ethernet controllers
+
+maintainers:
+  - Oleksij Rempel <o.rempel@pengutronix.de>
+
+description: |
+  Device tree properties for hard wired SMSC95xx compatible USB Ethernet
+  controller.
+
+allOf:
+  - $ref: ethernet-controller.yaml#
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - usb424,9500   # SMSC9500 USB Ethernet Device
+          - usb424,9505   # SMSC9505 USB Ethernet Device
+          - usb424,9530   # SMSC LAN9530 USB Ethernet Device
+          - usb424,9730   # SMSC LAN9730 USB Ethernet Device
+          - usb424,9900   # SMSC9500 USB Ethernet Device (SAL10)
+          - usb424,9901   # SMSC9505 USB Ethernet Device (SAL10)
+          - usb424,9902   # SMSC9500A USB Ethernet Device (SAL10)
+          - usb424,9903   # SMSC9505A USB Ethernet Device (SAL10)
+          - usb424,9904   # SMSC9512/9514 USB Hub & Ethernet Device (SAL10)
+          - usb424,9905   # SMSC9500A USB Ethernet Device (HAL)
+          - usb424,9906   # SMSC9505A USB Ethernet Device (HAL)
+          - usb424,9907   # SMSC9500 USB Ethernet Device (Alternate ID)
+          - usb424,9908   # SMSC9500A USB Ethernet Device (Alternate ID)
+          - usb424,9909   # SMSC9512/9514 USB Hub & Ethernet Devic.  ID)
+          - usb424,9e00   # SMSC9500A USB Ethernet Device
+          - usb424,9e01   # SMSC9505A USB Ethernet Device
+          - usb424,9e08   # SMSC LAN89530 USB Ethernet Device
+          - usb424,ec00   # SMSC9512/9514 USB Hub & Ethernet Device
+
+  reg: true
+  local-mac-address: true
+  mac-address: true
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    usb {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        ethernet@1 {
+            compatible = "usb424,9e00";
+            reg = <1>;
+            local-mac-address = [00 00 00 00 00 00];
+        };
+    };