rockchip: dts: tinker: migrate the dm-pre-reloc tag into -u-boot dts

Migrate all the "u-boot,dm-pre-reloc" tag from rk3288-tinker.dts
into rk3288-tinker-u-boot.dtsi.
When both board level and soc level '-u-boot.dtsi' files exist,
we need to include the soc level 'rk3288-u-boot.dtsi' manually.

Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/arch/arm/dts/rk3288-tinker-u-boot.dtsi b/arch/arm/dts/rk3288-tinker-u-boot.dtsi
new file mode 100644
index 0000000..cf961b3
--- /dev/null
+++ b/arch/arm/dts/rk3288-tinker-u-boot.dtsi
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019 Rockchip Electronics Co., Ltd
+ */
+
+#include "rk3288-u-boot.dtsi"
+
+&pinctrl {
+	u-boot,dm-pre-reloc;
+};
+
+&uart2 {
+	u-boot,dm-pre-reloc;
+};
+
+&sdmmc {
+	u-boot,dm-pre-reloc;
+};
+
+&emmc {
+	u-boot,dm-pre-reloc;
+};
+
+&gpio3 {
+	u-boot,dm-pre-reloc;
+};
+
+&gpio8 {
+	u-boot,dm-pre-reloc;
+};