dt-bindings: mmc: renesas_sdhi: Add r8a7744 support

Add support for r8a7744 SoC. Renesas RZ/G1N (R8A7744) SDHI is identical
to the R-Car Gen2 family.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Chris Paterson <Chris.Paterson2@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/tmio_mmc.txt

@@ -16,6 +16,7 @@ Required properties:
 		"renesas,sdhi-r8a73a4" - SDHI IP on R8A73A4 SoC
 		"renesas,sdhi-r8a7740" - SDHI IP on R8A7740 SoC
 		"renesas,sdhi-r8a7743" - SDHI IP on R8A7743 SoC
+		"renesas,sdhi-r8a7744" - SDHI IP on R8A7744 SoC
 		"renesas,sdhi-r8a7745" - SDHI IP on R8A7745 SoC
 		"renesas,sdhi-r8a774a1" - SDHI IP on R8A774A1 SoC
 		"renesas,sdhi-r8a7778" - SDHI IP on R8A7778 SoC