ARM: dts: r8a7794: Use R-Car SDHI Gen2 fallback compat string

Use newly added R-Car SDHI Gen2 fallback compat string
in the DT of the r8a7794 SoC.

This should have no run-time effect as the driver matches against
the per-SoC compat string before considering the fallback compat string.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a7794.dtsi

@@ -792,7 +792,8 @@ mmcif0: mmc@ee200000 {
 	};
 
 	sdhi0: sd@ee100000 {
-		compatible = "renesas,sdhi-r8a7794";
+		compatible = "renesas,sdhi-r8a7794",
+			     "renesas,rcar-gen2-sdhi";
 		reg = <0 0xee100000 0 0x328>;
 		interrupts = <GIC_SPI 165 IRQ_TYPE_LEVEL_HIGH>;
 		clocks = <&cpg CPG_MOD 314>;
@@ -806,7 +807,8 @@ sdhi0: sd@ee100000 {
 	};
 
 	sdhi1: sd@ee140000 {
-		compatible = "renesas,sdhi-r8a7794";
+		compatible = "renesas,sdhi-r8a7794",
+			     "renesas,rcar-gen2-sdhi";
 		reg = <0 0xee140000 0 0x100>;
 		interrupts = <GIC_SPI 167 IRQ_TYPE_LEVEL_HIGH>;
 		clocks = <&cpg CPG_MOD 312>;
@@ -820,7 +822,8 @@ sdhi1: sd@ee140000 {
 	};
 
 	sdhi2: sd@ee160000 {
-		compatible = "renesas,sdhi-r8a7794";
+		compatible = "renesas,sdhi-r8a7794",
+			     "renesas,rcar-gen2-sdhi";
 		reg = <0 0xee160000 0 0x100>;
 		interrupts = <GIC_SPI 168 IRQ_TYPE_LEVEL_HIGH>;
 		clocks = <&cpg CPG_MOD 311>;