added set_reboot_needed function and use it

lib/utils.sh

@@ -61,4 +61,16 @@ set_system_proxy()
 export -f set_system_proxy
 
 
+# ------------------------------------------------------------------------------
+# Set a reboot nedeed flag to display a warning at the end
+set_reboot_needed()
+{
+    if [[ $NEED_REBOOT==true ]]; then
+        # Reboot flag already set, nothing to do
+        return 0
+    else
+        export NEED_REBOOT=true
+    fi
+}
+
 # EOF