rockchip: rk3399: orangepi: Add init value for vdd_log

We should set the init value when vdd_log is enabled, or else the
vdd_log output voltage may not in soc required range.

Signed-off-by: Kever Yang <kever.yang@rock-chips.com>

arch/arm/dts/rk3399-orangepi-u-boot.dtsi

@@ -5,3 +5,7 @@
 
 #include "rk3399-u-boot.dtsi"
 #include "rk3399-sdram-ddr3-1333.dtsi"
+
+&vdd_log {
+	regulator-init-microvolt = <950000>;
+};