Fix bad expression causing plugin load failure

git-svn-id: https://svn.apache.org/repos/asf/maven/maven-1/plugins/trunk@113754 13f79535-47bb-0310-9956-ffa450edef68

shell/plugin.jelly

@@ -61,7 +61,7 @@ case "$state" in
 
 
       <j:choose>
-        <j:when test="${maven.shell.zdh.nodesc = 'true'}">
+        <j:when test="${maven.shell.zdh.nodesc == 'true'}">
            <j:set var="desc" value="${mavenSession.getGoalDescription(goal)}"/>
            <j:set var="escdesc" value='${desc.replaceAll(":","\\:")}'/>
            <j:set var="point" value="'"/>