ARM: dts: rockchip: add SPI flash node for rk3288-veyron

This is a standard binding for describing SPI flash that can be
identified by reading their JEDEC ID. Let's use it.

Tested on Veyron Jaq.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm/boot/dts/rk3288-veyron.dtsi

@@ -383,6 +383,12 @@ &spi2 {
 	status = "okay";
 
 	rx-sample-delay-ns = <12>;
+
+	flash@0 {
+		compatible = "jedec,spi-nor";
+		spi-max-frequency = <50000000>;
+		reg = <0>;
+	};
 };
 
 &tsadc {