dt-bindings: arm: renesas: Add R-Car M3-N ULCB with Kingfisher

Document the use of the Kingfisher expansion board with the R-Car
Starter Kit Pro equipped with an R-Car M3-N SoC.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20191016151109.30747-1-geert+renesas@glider.be

Documentation/devicetree/bindings/arm/renesas.yaml

@@ -211,9 +211,11 @@ properties:
           - enum:
               - renesas,h3ulcb
               - renesas,m3ulcb
+              - renesas,m3nulcb
           - enum:
               - renesas,r8a7795
               - renesas,r8a7796
+              - renesas,r8a77965
 
       - description: R-Car M3-N (R8A77965)
         items: