sw: "Current Index" doesn't make sense in context menu

This string is used in 2 places now, in the menu as a sub-item of
"Tools->Update" where it fits in, and in the context menu when
right-clicking on an index, where it clearly doesn't.

(regression from 447c3135)

Change-Id: I280f6c806d543f2fc1fff00976e5007b44b6452b

officecfg/registry/data/org/openoffice/Office/UI/WriterCommands.xcu

@@ -183,6 +183,9 @@
         <prop oor:name="Label" oor:type="xs:string">
           <value xml:lang="en-US">Current ~Index</value>
         </prop>
+        <prop oor:name="PopupLabel" oor:type="xs:string">
+          <value xml:lang="en-US">Update index</value>
+        </prop>
         <prop oor:name="Properties" oor:type="xs:int">
           <value>1</value>
         </prop>