dt-bindings: mmc: renesas,sdhi: Add r8a774e1 support

Document SDHI controller for RZ/G2H (R8A774E1) SoC, which is compatible
with R-Car Gen3 SoC family.
Signed-off-by: NLad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: NMarian-Cristian Rotariu <marian-cristian.rotariu.rb@bp.renesas.com>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200809192001.19156-1-prabhakar.mahadev-lad.rj@bp.renesas.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/renesas,sdhi.yaml

@@ -50,6 +50,7 @@ properties:
               - renesas,sdhi-r8a774a1 # RZ/G2M
               - renesas,sdhi-r8a774b1 # RZ/G2N
               - renesas,sdhi-r8a774c0 # RZ/G2E
+              - renesas,sdhi-r8a774e1 # RZ/G2H
               - renesas,sdhi-r8a7795  # R-Car H3
               - renesas,sdhi-r8a7796  # R-Car M3-W
               - renesas,sdhi-r8a77961 # R-Car M3-W+