Fix ps memory leak caused by deallocate prepare

src/sql/engine/prepare/ob_deallocate_executor.cpp

@@ -29,8 +29,8 @@ int ObDeallocateExecutor::execute(ObExecContext& ctx, ObDeallocateStmt& stmt)
   } else {
     if (OB_FAIL(ctx.get_my_session()->remove_prepare(stmt.get_prepare_name()))) {
       LOG_WARN("failed to remove prepare", K(stmt.get_prepare_name()), K(ret));
-    } else if (OB_FAIL(ctx.get_my_session()->remove_ps_session_info(stmt.get_prepare_id()))) {
-      LOG_WARN("failed to remove prepare", K(stmt.get_prepare_id()), K(ret));
+    } else if (OB_FAIL(ctx.get_my_session()->close_ps_stmt(stmt.get_prepare_id()))) {
+      LOG_WARN("fail to deallocate ps stmt", K(ret), K(stmt.get_prepare_id()));
     } else { /*do nothing*/
     }
   }