arm: dts: rockchip: move all rk3288 u-boot specific properties in separate dtsi files

In order to sync rk3288.dtsi from Linux it needed to
move all u-boot specific properties in separate dtsi files.

Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/arch/arm/dts/rk3288-popmetal-u-boot.dtsi b/arch/arm/dts/rk3288-popmetal-u-boot.dtsi
index 8ac7840..3782253 100644
--- a/arch/arm/dts/rk3288-popmetal-u-boot.dtsi
+++ b/arch/arm/dts/rk3288-popmetal-u-boot.dtsi
@@ -5,6 +5,17 @@
 
 #include "rk3288-u-boot.dtsi"
 
+&dmc {
+	rockchip,pctl-timing = <0x29a 0xc8 0x1f8 0x42 0x4e 0x4 0xea 0xa
+		0x5 0x0 0xa 0x7 0x19 0x24 0xa 0x7
+		0x5 0xa 0x5 0x200 0x5 0x10 0x40 0x0
+		0x1 0x7 0x7 0x4 0xc 0x43 0x100 0x0
+		0x5 0x0>;
+	rockchip,phy-timing = <0x48f9aab4 0xea0910 0x1002c200
+		0xa60 0x40 0x10 0x0>;
+	rockchip,sdram-params = <0x30B25564 0x627 3 666000000 3 9 1>;
+};
+
 &pinctrl {
 	u-boot,dm-pre-reloc;
 };