Replace legacy header usage to fix compilation

stream.h is no longer provided on modern systems, use iostream instead.

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>

--- zsafe-2.1.3-r1.orig/zsafe.h
+++ zsafe-2.1.3-r1/zsafe.h
@@ -16,7 +16,7 @@
 
 #ifndef WIN32
 #ifndef DESKTOP
-#include <stream.h>
+#include <iostream>
 #else
 #include <sstream>
 #endif