arm64: dts: rockchip: Enable MTD Flash on rk3399-roc-pc

rk3399-roc-pc has 16 MB SPI NOR Flash, enable it.
Signed-off-by: Markus Reichl <m.reichl@fivetechno.de>
Link: https://lore.kernel.org/r/94f44e1d-86c6-1e32-aa63-56edbd7d75f5@fivetechno.deSigned-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm64/boot/dts/rockchip/rk3399-roc-pc.dtsi

@@ -699,6 +699,16 @@ &sdhci {
 	status = "okay";
 };
 
+&spi1 {
+	status = "okay";
+
+	flash@0 {
+		compatible = "jedec,spi-nor";
+		reg = <0>;
+		spi-max-frequency = <10000000>;
+	};
+};
+
 &tcphy0 {
 	status = "okay";
 };