remove unneeded call to wlr_scene_rect_set_color()

wlr_scene_rect_create() requires a color as parameter

dwl.c

@@ -1361,7 +1361,6 @@ mapnotify(struct wl_listener *listener, void *data)
 	for (i = 0; i < 4; i++) {
 		c->border[i] = wlr_scene_rect_create(c->scene, 0, 0, bordercolor);
 		c->border[i]->node.data = c;
-		wlr_scene_rect_set_color(c->border[i], bordercolor);
 	}
 
 	/* Initialize client geometry with room for border */