bikeshed markup fix

Author: svgeesus

css-fonts-4/Overview.bs

@@ -3560,7 +3560,7 @@ to produce more harmonized forms.</p>
 
 <p>Individual values have the following meanings:</p>
 
-<dl>
+<dl dfn-for="font-variant-ligatures">
 	<dt><dfn id="font-variant-ligatures-normal-value" title="normal!!font-variant-ligatures">normal</dfn></dt>
 <dd>A value of <span title="normal!!font-variant-ligatures">'normal'</span>
 specifies that common default features are enabled,