rockchip: rk356x-generic: Add support for SPI flash

Add support for booting from SPI flash using the generic RK3566/RK3568
target.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/arch/arm/dts/rk3568-generic-u-boot.dtsi b/arch/arm/dts/rk3568-generic-u-boot.dtsi
index 6e8307e..fd7f536 100644
--- a/arch/arm/dts/rk3568-generic-u-boot.dtsi
+++ b/arch/arm/dts/rk3568-generic-u-boot.dtsi
@@ -1,3 +1,10 @@
 // SPDX-License-Identifier: (GPL-2.0+ OR MIT)
 
 #include "rk356x-u-boot.dtsi"
+
+&sfc {
+	flash@0 {
+		bootph-pre-ram;
+		bootph-some-ram;
+	};
+};