dt-bindings: dma: renesas,rcar-dmac: Document R8A774E1 bindings

Renesas RZ/G2H (R8A774E1) SoC also has the R-Car gen3 compatible
DMA controllers, therefore document RZ/G2H specific bindings.
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/1594676120-5862-5-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Documentation/devicetree/bindings/dma/renesas,rcar-dmac.yaml

@@ -23,6 +23,7 @@ properties:
           - renesas,dmac-r8a774a1 # RZ/G2M
           - renesas,dmac-r8a774b1 # RZ/G2N
           - renesas,dmac-r8a774c0 # RZ/G2E
+          - renesas,dmac-r8a774e1 # RZ/G2H
           - renesas,dmac-r8a7790  # R-Car H2
           - renesas,dmac-r8a7791  # R-Car M2-W
           - renesas,dmac-r8a7792  # R-Car V2H