Correct documentation for keyboardEventTarget.

src/ol/interaction/keyboardzoominteraction.js

@@ -15,7 +15,7 @@ goog.require('ol.interaction.Interaction');
  * Note that, although this interaction is by default included in maps,
  * the keys can only be used when browser focus is on the element to which
  * the keyboard events are attached. By default, this is the map div,
- * though you can change this with the `keyboardTargetElement` in
+ * though you can change this with the `keyboardEventTarget` in
  * {@link ol.Map}. `document` never loses focus but, for any other element,
  * focus will have to be on, and returned to, this element if the keys are to
  * function.