[2225_xfrout] update description of zonename

src/bin/xfrout/xfrout.spec.pre.in

@@ -136,7 +136,7 @@
             "item_optional": false,
             "item_default": {},
             "item_title": "Zone name",
-            "item_description": "Zone name for Xfrout statistics",
+            "item_description": "A actual zone name or special zone name _SERVER_ representing an entire server",
             "map_item_spec": [
               {
                 "item_name": "notifyoutv4",