of/flattree: merge of_get_flat_dt_root

Merge common code between PowerPC and MicroBlaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Michal Simek <monstr@monstr.eu>
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index dd9057c..f41d739 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -83,3 +83,19 @@
 
 	return rc;
 }
+
+/**
+ * of_get_flat_dt_root - find the root node in the flat blob
+ */
+unsigned long __init of_get_flat_dt_root(void)
+{
+	unsigned long p = ((unsigned long)initial_boot_params) +
+		initial_boot_params->off_dt_struct;
+
+	while (*((u32 *)p) == OF_DT_NOP)
+		p += 4;
+	BUG_ON(*((u32 *)p) != OF_DT_BEGIN_NODE);
+	p += 4;
+	return _ALIGN(p + strlen((char *)p) + 1, 4);
+}
+