ARM: dts: rockchip: fix compatible string for eMMC node of rk3228 SoC

This adds amend compatible content for eMMC of RK3228 SoC.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm/boot/dts/rk322x.dtsi

@@ -528,7 +528,7 @@ tsadc: tsadc@11150000 {
 	};
 
 	emmc: dwmmc@30020000 {
-		compatible = "rockchip,rk3288-dw-mshc";
+		compatible = "rockchip,rk3228-dw-mshc", "rockchip,rk3288-dw-mshc";
 		reg = <0x30020000 0x4000>;
 		interrupts = <GIC_SPI 14 IRQ_TYPE_LEVEL_HIGH>;
 		clock-frequency = <37500000>;