dm: Add a function to create a 'live' device tree

This function converts the flat device tree into a hierarchical one with
C structures and pointers. This is easier to access.

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

include/of_live.h

@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2017 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ * Support for a 'live' (as opposed to flat) device tree
+ */
+
+#ifndef _OF_LIVE_H
+#define _OF_LIVE_H
+
+struct device_node;
+
+/**
+ * of_live_build() - build a live (hierarchical) tree from a flat DT
+ *
+ * @fdt_blob: Input tree to convert
+ * @rootp: Returns live tree that was created
+ * @return 0 if OK, -ve on error
+ */
+int of_live_build(const void *fdt_blob, struct device_node **rootp);
+
+#endif