dm: arm: Bring in skeleton64 device tree file from Linux

Backport of kernel commits:
	7c14f6c719de092d69c81877786e83ce7ae1a860
	35faad2a1563b3d4dc983a82ac41033fe053870c

Signed-off-by: Haikun Wang <Haikun.Wang@freescale.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/dts/skeleton64.dtsi b/arch/arm/dts/skeleton64.dtsi
new file mode 100644
index 0000000..b5d7f36
--- /dev/null
+++ b/arch/arm/dts/skeleton64.dtsi
@@ -0,0 +1,13 @@
+/*
+ * Skeleton device tree in the 64 bits version; the bare minimum
+ * needed to boot; just include and add a compatible value.  The
+ * bootloader will typically populate the memory node.
+ */
+
+/ {
+	#address-cells = <2>;
+	#size-cells = <2>;
+	chosen { };
+	aliases { };
+	memory { device_type = "memory"; reg = <0 0 0 0>; };
+};