Remove HB_DISALLOW_COPY_AND_ASSIGN from hb_ot_shape_planner_t

It was arbitrary that this struct had it and not dozens of others.

src/hb-ot-shape.hh

@@ -102,9 +102,6 @@ struct hb_ot_shape_planner_t
   HB_INTERNAL void compile (hb_ot_shape_plan_t &plan,
 			    const int          *coords,
 			    unsigned int        num_coords);
-
-  private:
-  HB_DISALLOW_COPY_AND_ASSIGN (hb_ot_shape_planner_t);
 };