dt-bindings: usb: dwc2: add disable-over-current

The driver parses disable-over-current protection and some
implementations use it (e.g. Altera Stratix10), so document it in the
bindings.

Acked-by: Rob Herring <[e-mail]>
Signed-off-by: Krzysztof Kozlowski <[e-mail]>
Signed-off-by: Dinh Nguyen <[e-mail]>

Documentation/devicetree/bindings/usb/dwc2.yaml

···
     items:
       - const: otg
 
+  disable-over-current:
+    type: boolean
+    description: whether to disable detection of over-current condition.
+
   iommus:
     maxItems: 1