Adding option for openssh to disable dns resolvings

Change-Id: I31a263ba044745fd16a3574bc83133b32f98b6a2
diff --git a/README.rst b/README.rst
index a3625c7..5a87430 100644
--- a/README.rst
+++ b/README.rst
@@ -17,6 +17,7 @@
     openssh:
       client:
         enabled: true
+        use_dns: False
         user:
           root:
             enabled: true