Remove FAQ link in header when disabled

lms/templates/navigation.html

@@ -71,7 +71,9 @@ site_status_msg = get_site_status_msg(course_id)
         <a href="#" class="dropdown" aria-haspopup="true" aria-expanded="false"><span class="sr">${_("More options dropdown")}</span> &#9662;</a>
         <ul class="dropdown-menu" aria-label="More Options" role="menu">
           <%block name="navigation_dropdown_menu_links" >
-            <li><a href="${marketing_link('FAQ')}">${_("Help")}</a></li>
+            % if settings.MKTG_URL_LINK_MAP.get('FAQ'):
+              <li><a href="${marketing_link('FAQ')}">${_("Help")}</a></li>
+            % endif
           </%block>
           <li><a href="${reverse('logout')}" role="menuitem">${_("Log Out")}</a></li>
         </ul>