state_tracker: Free Labels for querry and tranform_feedback

Memory leaks were observed on iris with GL_KHR_debug.

Signed-off-by: Yevhenii Kolesnikov <yevhenii.kolesnikov@globallogic.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>

src/mesa/state_tracker/st_cb_queryobj.c

@@ -86,6 +86,7 @@ st_DeleteQuery(struct gl_context *ctx, struct gl_query_object *q)
 
    free_queries(pipe, stq);
 
+   free(q->Label);
    free(stq);
 }
 

src/mesa/state_tracker/st_cb_xformfb.c

@@ -100,6 +100,7 @@ st_delete_transform_feedback(struct gl_context *ctx,
       _mesa_reference_buffer_object(ctx, &sobj->base.Buffers[i], NULL);
    }
 
+   free(obj->Label);
    free(obj);
 }