of/flattree: merge find_flat_dt_string and initial_boot_params

Merge common code between Microblaze and PowerPC.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Michal Simek <monstr@monstr.eu>

drivers/of/fdt.c

@@ -0,0 +1,21 @@
+/*
+ * Functions for working with the Flattened Device Tree data format
+ *
+ * Copyright 2009 Benjamin Herrenschmidt, IBM Corp
+ * benh@kernel.crashing.org
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ */
+
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+
+struct boot_param_header *initial_boot_params;
+
+char *find_flat_dt_string(u32 offset)
+{
+	return ((char *)initial_boot_params) +
+		initial_boot_params->off_dt_strings + offset;
+}