add removal of .help-inline to the migration guide; fixes #12539

docs/migration.html

@@ -400,6 +400,11 @@ lead: "Guidance on how to upgrade from Bootstrap v2.x to v3.x with emphasis on m
           <td><code>.nav-list</code> <code>.nav-header</code></td>
           <td>No direct equivalent, but <a href="../components/#list-group">list groups</a> and <a href="../javascript/#collapse"><code>.panel-group</code>s</a> are similar.</td>
         </tr>
+        <tr>
+          <td>Inline help for form controls</td>
+          <td><code>.help-inline</code></td>
+          <td>No exact equivalent, but <code>.help-block</code> is similar.</td>
+        </tr>
       </tbody>
     </table>
   </div><!-- /.table-responsive -->