Fix buffer initalisation

Initialise the buffer tail with random data instead of
given value.
diff --git a/library/platform_util.c b/library/platform_util.c
index f011032..0eaca83 100644
--- a/library/platform_util.c
+++ b/library/platform_util.c
@@ -88,7 +88,7 @@
 
     /* Perform a pair of memset operations from random locations with
      * random data */
-    memset( (void *) ( (unsigned char *) ptr + start_offset ), value,
+    memset( (void *) ( (unsigned char *) ptr + start_offset ), data,
             ( num - start_offset ) );
     memset( (void *) ptr, data, start_offset );