arm64: dts: rockchip: set stdout-path on helios64

set the default output path to uart2
Signed-off-by: Dennis Gilmore <dgilmore@redhat.com>
Link: https://lore.kernel.org/r/20210715025635.70452-2-dgilmore@redhat.comSigned-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm64/boot/dts/rockchip/rk3399-kobol-helios64.dts

@@ -43,6 +43,10 @@ avdd_1v8_s0: avdd-1v8-s0 {
 		vin-supply = <&vcc3v3_sys_s3>;
 	};
 
+	chosen {
+		stdout-path = "serial2:1500000n8";
+	};
+
 	clkin_gmac: external-gmac-clock {
 		compatible = "fixed-clock";
 		clock-frequency = <125000000>;