fix subdirectory links

Author: Vladimir Kotal

opengrok-web/src/main/webapp/WEB-INF/tags/repository.tag

@@ -57,7 +57,7 @@ Portions Copyright (c) 2019, Krystof Tulinger <[email protected]>.
 
 <tr>
     <td class="name ${isSubrepository ? "subrepository" : "repository"}">
-        <a href="${pageContext.request.getContextPath()}${Prefix.XREF_P.toString()}/${project.name}"
+        <a href="${pageContext.request.getContextPath()}${Prefix.XREF_P.toString()}/${name}"
            title="Xref for project ${Util.htmlize(name)}">
             ${Util.htmlize(name)}
         </a>