dt-bindings: watchdog: renesas,wdt: Document RZ/V2N (R9A09G056) support

Document support for the watchdog IP found on the Renesas RZ/V2N
(R9A09G056) SoC. The watchdog IP is identical to that on RZ/V2H(P),
so `renesas,r9a09g057-wdt` will be used as a fallback compatible,
enabling reuse of the existing driver without changes.

Signed-off-by: Lad Prabhakar <[email protected]>
Reviewed-by: Geert Uytterhoeven <[email protected]>
Acked-by: Conor Dooley <[email protected]>
Reviewed-by: Guenter Roeck <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Guenter Roeck <[email protected]>
Signed-off-by: Wim Van Sebroeck <[email protected]>

Author: prabhakarlad

Documentation/devicetree/bindings/watchdog/renesas,wdt.yaml

@@ -76,7 +76,9 @@ properties:
           - const: renesas,rcar-gen4-wdt # R-Car Gen4
 
       - items:
-          - const: renesas,r9a09g047-wdt # RZ/G3E
+          - enum:
+              - renesas,r9a09g047-wdt # RZ/G3E
+              - renesas,r9a09g056-wdt # RZ/V2N
           - const: renesas,r9a09g057-wdt # RZ/V2H(P)
 
       - const: renesas,r9a09g057-wdt       # RZ/V2H(P)