dt-bindings: irq: sun7i-nmi: Add binding documentation for the V3s NMI

The V3s NMI controller seems register-compatible with the A80 (sun9i).
Add new items for the compatible string, with an entry specific to the V3s
and the A80 entry.
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20201206165131.1041983-2-contact@paulk.fr

Documentation/devicetree/bindings/interrupt-controller/allwinner,sun7i-a20-sc-nmi.yaml

@@ -29,6 +29,9 @@ properties:
       - items:
           - const: allwinner,sun8i-a83t-r-intc
           - const: allwinner,sun6i-a31-r-intc
+      - items:
+          - const: allwinner,sun8i-v3s-nmi
+          - const: allwinner,sun9i-a80-nmi
       - const: allwinner,sun9i-a80-nmi
       - items:
           - const: allwinner,sun50i-a64-r-intc