Update protectionPreRequisites For Use w/o CHATTR

protectionPreRequisites returns non ZERO code if 
- ENABLE_CHATTR false
 - chattr not available 
Because [ false == true ] (L139) will return a non zero rc.
Adds a return 0 if we reach eventually the end of the func.

scripts/cnode-helper-scripts/cntools.library

@@ -149,6 +149,7 @@ protectionPreRequisites() {
     fi
     rm -f "${TMP_DIR}"/test
   fi
+  return 0
 }
 
 # Command     : safeDel [path]