dt-bindings: memory: renesas,rpc-if: Document R-Car V4H support

Document support for the SPI Multi I/O Bus Controller (RPC-IF) in the
R-Car V4H SoC.

Signed-off-by: Hai Pham <[e-mail]>
Signed-off-by: Geert Uytterhoeven <[e-mail]>
Reviewed-by: Wolfram Sang <[e-mail]>
Reviewed-by: Rob Herring <[e-mail]>
Link: https://lore.kernel.org/r/c268c[e-mail]
Signed-off-by: Krzysztof Kozlowski <[e-mail]>

Documentation/devicetree/bindings/memory-controllers/renesas,rpc-if.yaml

···
 
       - items:
           - enum:
+              - renesas,r8a779g0-rpc-if       # R-Car V4H
+          - const: renesas,rcar-gen4-rpc-if   # a generic R-Car gen4 device
+
+      - items:
+          - enum:
               - renesas,r9a07g043-rpc-if      # RZ/G2UL
               - renesas,r9a07g044-rpc-if      # RZ/G2{L,LC}
               - renesas,r9a07g054-rpc-if      # RZ/V2L