Null username support is removed from Get Channel Auth command

Change-Id: I9340c9da524831a68192424c68efc7a4910407d7
Signed-off-by: Tom Joseph <tomjoseph@in.ibm.com>
diff --git a/command/channel_auth.cpp b/command/channel_auth.cpp
index 1b5b604..1ae006b 100644
--- a/command/channel_auth.cpp
+++ b/command/channel_auth.cpp
@@ -32,7 +32,7 @@
     response->perMessageAuth = 0; // Per-message Authentication is enabled
     response->userAuth = 0;       // User Level Authentication is enabled
     response->nonNullUsers = 1;   // Non-null usernames enabled
-    response->nullUsers = 1;      // Null usernames enabled
+    response->nullUsers = 0;      // Null usernames disabled
     response->anonymousLogin = 0; // Anonymous Login disabled
 
     response->reserved4 = 0;