rockchip: rk3588-rock-5b: Include eMMC node in SPL dtb

Add sdhci node to SPL and u-boot,spl-boot-order. Also add more supported
mmc modes and pinctrl.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/arch/arm/dts/rk3588s-u-boot.dtsi b/arch/arm/dts/rk3588s-u-boot.dtsi
index 76a8ffe..5201ba2 100644
--- a/arch/arm/dts/rk3588s-u-boot.dtsi
+++ b/arch/arm/dts/rk3588s-u-boot.dtsi
@@ -65,6 +65,10 @@
 	u-boot,spl-fifo-mode;
 };
 
+&sdhci {
+	bootph-pre-ram;
+};
+
 &uart2 {
 	clock-frequency = <24000000>;
 	bootph-pre-ram;