tegra: Use a U-Boot-specific .dtsi file

With the new device-tree rules it is possible to put device-tree changes
needed by U-Boot into their own file. As an example of this approach, move
Tegra over to use it.

Signed-off-by: Simon Glass <sjg@chromium.org>

arch/arm/dts/tegra124-nyan-big-u-boot.dtsi

@@ -0,0 +1,15 @@
+/*
+ * Copyright (C) 2016 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+/ {
+	host1x@50000000 {
+		u-boot,dm-pre-reloc;
+		dc@54200000 {
+			u-boot,dm-pre-reloc;
+		};
+	};
+};

arch/arm/dts/tegra124-nyan-big.dts

@@ -27,9 +27,7 @@
 	};
 
 	host1x@50000000 {
-		u-boot,dm-pre-reloc;
 		dc@54200000 {
-			u-boot,dm-pre-reloc;
 			display-timings {
 				timing@0 {
 					clock-frequency = <69500000>;

arch/arm/dts/tegra20-u-boot.dtsi

@@ -0,0 +1,8 @@
+/ {
+	host1x@50000000 {
+		u-boot,dm-pre-reloc;
+		dc@54200000 {
+			u-boot,dm-pre-reloc;
+		};
+	};
+};

arch/arm/dts/tegra20.dtsi

@@ -10,7 +10,6 @@
 	interrupt-parent = <&lic>;
 
 	host1x@50000000 {
-		u-boot,dm-pre-reloc;
 		compatible = "nvidia,tegra20-host1x", "simple-bus";
 		reg = <0x50000000 0x00024000>;
 		interrupts = <GIC_SPI 65 IRQ_TYPE_LEVEL_HIGH>, /* syncpt */
@@ -78,7 +77,6 @@
 		};
 
 		dc@54200000 {
-			u-boot,dm-pre-reloc;
 			compatible = "nvidia,tegra20-dc";
 			reg = <0x54200000 0x00040000>;
 			interrupts = <GIC_SPI 73 IRQ_TYPE_LEVEL_HIGH>;