dtoc: Allow inserting a list of nodes into another

Provide a way to specify a phandle list of nodes which are to be inserted
into an existing node.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/dtoc/test/dtoc_test_copy.dts b/tools/dtoc/test/dtoc_test_copy.dts
index 85e2c34..36faa9b 100644
--- a/tools/dtoc/test/dtoc_test_copy.dts
+++ b/tools/dtoc/test/dtoc_test_copy.dts
@@ -11,6 +11,7 @@
 	#address-cells = <1>;
 	#size-cells = <1>;
 	reference = <&over>;	/* nake sure that the 'over' phandle exists */
+	copy-list = <&another &base>;
 
 	dest {
 		bootph-all;
@@ -46,7 +47,7 @@
 		};
 	};
 
-	base {
+	base: base {
 		compatible = "sandbox,i2c";
 		bootph-all;
 		#address-cells = <1>;
@@ -73,4 +74,15 @@
 			};
 		};
 	};
+
+	another: another {
+		new-prop = "hello";
+		earlier {
+			wibble = <2>;
+		};
+
+		later {
+			fibble = <3>;
+		};
+	};
 };