Update usb_ethernet.md (#667)

* Update usb_ethernet.md

Added an example

* Update usb_ethernet.md

Fixed

docs/usb_ethernet.md

@@ -81,3 +81,18 @@ By default, `kvmd-otgnet` will configure network connection between PiKVM and th
     ```
 
 5. Don't forget to `reboot`.
+    
+??? example "An example of what what the config would look like if you wanted the target to have inet access (Please edit to suit your needs):"
+    ```
+    otgnet:
+        firewall:
+            allow_tcp: [80, 443]
+            forward_iface: wlan0
+        commands:
+            post_start_cmd_append:
+                - "--dhcp-option=6,1.1.1.1,1.0.0.1"
+        iface:
+            ip_cmd:
+                - /usr/bin/ip
+            net: 10.65.0.0/28
+    ```