[css-images-3] Fix link

Author: fantasai

css-images-3/Overview.bs

@@ -25,6 +25,9 @@ Ignored Vars: start image, end image
 Link Defaults: css2 (property) display
 Include Can I Use Panels: yes
 </pre>
+<pre class=link-defaults>
+spec:svg; type:element; text:feimage
+</pre>
 
 Introduction {#intro}
 =====================