dt-bindings: mmc: tmio_mmc: Document Renesas R7S9210

Document support for the RZ/A2 (R7S9210) SoC.
Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/tmio_mmc.txt

@@ -13,6 +13,7 @@ Required properties:
 - compatible: should contain one or more of the following:
 		"renesas,sdhi-sh73a0" - SDHI IP on SH73A0 SoC
 		"renesas,sdhi-r7s72100" - SDHI IP on R7S72100 SoC
+		"renesas,sdhi-r7s9210" - SDHI IP on R7S9210 SoC
 		"renesas,sdhi-r8a73a4" - SDHI IP on R8A73A4 SoC
 		"renesas,sdhi-r8a7740" - SDHI IP on R8A7740 SoC
 		"renesas,sdhi-r8a7743" - SDHI IP on R8A7743 SoC
@@ -56,7 +57,7 @@ Required properties:
 	  "core" and "cd". If the controller only has 1 clock, naming is not
 	  required.
 	  Devices which have more than 1 clock are listed below:
-	  2: R7S72100
+	  2: R7S72100, R7S9210
 
 Optional properties:
 - pinctrl-names: should be "default", "state_uhs"