Merge libfdt into dtc.

Having pulled the libfdt repository into dtc, merge the makefiles and
testsuites so that they build together usefully.

tests/dumptrees.c

@@ -0,0 +1,49 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdint.h>
+
+#include <fdt.h>
+#include <libfdt.h>
+#include <libfdt_env.h>
+
+#include "testdata.h"
+
+struct {
+	void *blob;
+	const char *filename;
+} trees[] = {
+#define TREE(name)	{ &_##name, #name ".dtb" }
+	TREE(test_tree1),
+};
+
+#define NUM_TREES	(sizeof(trees) / sizeof(trees[0]))
+
+int main(int argc, char *argv[])
+{
+	int i;
+
+	for (i = 0; i < NUM_TREES; i++) {
+		void *blob = trees[i].blob;
+		const char *filename = trees[i].filename;
+		int size;
+		int fd;
+		int ret;
+
+		size = fdt_totalsize(blob);
+
+		printf("Tree \"%s\", %d bytes\n", filename, size);
+
+		fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
+		if (fd < 0)
+			perror("open()");
+
+		ret = write(fd, blob, size);
+		if (ret != size)
+			perror("write()");
+
+		close(fd);
+	}
+	exit(0);
+}