dt-bindings: usb: dwc2: add support for Amlogic A1 SoC USB peripheral

Provide the appropriate compatible string for the DWC2 IP that is found
inside the Amlogic A1 SoC and used in peripheral mode.

Signed-off-by: Dmitry Rokosov <[e-mail]>
Acked-by: Rob Herring <[e-mail]>
Reviewed-by: Martin Blumenstingl <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

Documentation/devicetree/bindings/usb/dwc2.yaml

···
               - amlogic,meson8b-usb
               - amlogic,meson-gxbb-usb
               - amlogic,meson-g12a-usb
+              - amlogic,meson-a1-usb
               - intel,socfpga-agilex-hsotg
           - const: snps,dwc2
       - const: amcc,dwc-otg