rockchip: gru: Add extra device-tree settings

Add some U-Boot-specific settings. These should really go in the
*u-boot.dtsi file, but it seems that rk3399 does not use that yet.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
diff --git a/arch/arm/dts/rk3399-gru-bob.dts b/arch/arm/dts/rk3399-gru-bob.dts
index 1ee0dc0..0e3d91f 100644
--- a/arch/arm/dts/rk3399-gru-bob.dts
+++ b/arch/arm/dts/rk3399-gru-bob.dts
@@ -7,6 +7,7 @@
 
 /dts-v1/;
 #include "rk3399-gru-chromebook.dtsi"
+#include "rk3399-sdram-lpddr3-samsung-4GB-1866.dtsi"
 
 / {
 	model = "Google Bob";