Cleanup for GCC-4.x
diff --git a/board/esd/du405/du405.c b/board/esd/du405/du405.c
index 7db2a60..26e8341 100644
--- a/board/esd/du405/du405.c
+++ b/board/esd/du405/du405.c
@@ -162,7 +162,7 @@
 {
 	int index;
 	int len;
-	unsigned char str[64];
+	char str[64];
 	int i = getenv_r ("serial#", str, sizeof (str));
 
 	puts ("Board: ");