soc: renesas: rcar-sysc: Document r8a7796 support

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

Documentation/devicetree/bindings/power/renesas,rcar-sysc.txt

@@ -14,6 +14,7 @@ Required properties:
       - "renesas,r8a7793-sysc" (R-Car M2-N)
       - "renesas,r8a7794-sysc" (R-Car E2)
       - "renesas,r8a7795-sysc" (R-Car H3)
+      - "renesas,r8a7796-sysc" (R-Car M3-W)
   - reg: Address start and address range for the device.
   - #power-domain-cells: Must be 1.