dt-bindings: can: renesas,rcar-canfd: R-Car V3U is R-Car Gen4

Despite the name, R-Car V3U is the first member of the R-Car Gen4
family. Hence generalize this by introducing a family-specific
compatible value for R-Car Gen4.

While at it, replace "both channels" by "all channels", as the numbers
of channels may differ from two.

Signed-off-by: Geert Uytterhoeven <[e-mail]>
Acked-by: Rob Herring <[e-mail]>
Link: https://lore.kernel.org/all/4dea4[e-mail]
Signed-off-by: Marc Kleine-Budde <[e-mail]>

Documentation/devicetree/bindings/net/can/renesas,rcar-canfd.yaml

···
 
       - items:
           - enum:
+              - renesas,r8a779a0-canfd     # R-Car V3U
+          - const: renesas,rcar-gen4-canfd # R-Car Gen4
+
+      - items:
+          - enum:
               - renesas,r9a07g043-canfd    # RZ/G2UL and RZ/Five
               - renesas,r9a07g044-canfd    # RZ/G2{L,LC}
               - renesas,r9a07g054-canfd    # RZ/V2L
           - const: renesas,rzg2l-canfd     # RZ/G2L family
-
-      - const: renesas,r8a779a0-canfd      # R-Car V3U
 
   reg:
     maxItems: 1
···
     $ref: /schemas/types.yaml#/definitions/flag
     description:
       The controller can operate in either CAN FD only mode (default) or
-      Classical CAN only mode.  The mode is global to both the channels.
+      Classical CAN only mode.  The mode is global to all channels.
       Specify this property to put the controller in Classical CAN only mode.
 
   assigned-clocks:
···
         properties:
           compatible:
             contains:
-              const: renesas,r8a779a0-canfd
+              const: renesas,rcar-gen4-canfd
     then:
       patternProperties:
         "^channel[2-7]$": false