rockchip: dts: rk3399-evb: add sdmmc node

The sdmmc node is missing after the dts sync patch:
  167efc2c7a arm64: dts: rk3399: Sync v5.7-rc1 from Linux
But we still need it for boot from SD card, so add it.

Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/arch/arm/dts/rk3399-evb-u-boot.dtsi b/arch/arm/dts/rk3399-evb-u-boot.dtsi
index 1be54fe..8056dc8 100644
--- a/arch/arm/dts/rk3399-evb-u-boot.dtsi
+++ b/arch/arm/dts/rk3399-evb-u-boot.dtsi
@@ -37,3 +37,16 @@
 	dr_mode = "host";
 	status = "okay";
 };
+
+&sdmmc {
+	u-boot,dm-pre-reloc;
+	bus-width = <4>;
+	cap-mmc-highspeed;
+	cap-sd-highspeed;
+	cd-gpios = <&gpio0 7 GPIO_ACTIVE_LOW>;
+	disable-wp;
+	max-frequency = <150000000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&sdmmc_clk &sdmmc_cmd &sdmmc_bus4>;
+	status = "okay";
+};