docs: Add bold style for <dt><code> elements

Add bolding for <dt><code> elements to make them "stick out" on the
page rather that just a stream of text where the elements only differ
by slightly different font style.

docs/generic.css

@@ -27,6 +27,10 @@ dt {
   margin-right: 2em;
 }
 
+dt code {
+  font-weight: bold;
+}
+
 dl dd {
   margin-left: 2em;
   margin-right: 2em;