ARM: dts: rk3328-rock64: Add SPI Flash support

Add U-Boot SPI Flash support for the PINE64 Rock64 board

Signed-off-by: Johannes Krottmayer <krjdev@gmail.com>
Cc: Matwey V. Kornilov <matwey.kornilov@gmail.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/arch/arm/dts/rk3328-rock64-u-boot.dtsi b/arch/arm/dts/rk3328-rock64-u-boot.dtsi
index f076075..7340ef9 100644
--- a/arch/arm/dts/rk3328-rock64-u-boot.dtsi
+++ b/arch/arm/dts/rk3328-rock64-u-boot.dtsi
@@ -46,3 +46,9 @@
 &vcc_sd {
 	u-boot,dm-spl;
 };
+
+&spi0 {
+	spi_flash: spiflash@0 {
+		u-boot,dm-pre-reloc;
+	};
+};