expo: Adjust how menu items are highlighted

At present when the user moves to a new menu item, the menu code
handles this immediately. This means it is not possible to use an expo
action to effect the same change.

Update this so that EXPOACT_POINT_ITEM is handled in cedit_do_action().

Expand the test to cover this.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/boot/cedit.c b/boot/cedit.c
index eac851b..792ab6d 100644
--- a/boot/cedit.c
+++ b/boot/cedit.c
@@ -148,10 +148,17 @@
 int cedit_do_action(struct expo *exp, struct scene *scn,
 		    struct video_priv *vid_priv, struct expo_action *act)
 {
+	int ret;
+
 	switch (act->type) {
 	case EXPOACT_NONE:
-	case EXPOACT_POINT_ITEM:
 		return -EAGAIN;
+	case EXPOACT_POINT_ITEM:
+		ret = scene_menu_select_item(scn, scn->highlight_id,
+					     act->select.id);
+		if (ret)
+			return log_msg_ret("cdp", ret);
+		break;
 	case EXPOACT_POINT_OBJ:
 		scene_set_highlight_id(scn, act->select.id);
 		cedit_arange(exp, vid_priv, scn->id);