ART-tests: Remove DX-dependency from 570-checker-osr.

This test has already been working with D8, this CL only enables D8.

Test: art/test.py -r -b --host -t 570-checker-osr
      Tested locally with --target/--gcstress.
Bug: 65168732

Change-Id: I3d8094f50cc765efb57b59a96aff972f9d04441f
diff --git a/test/570-checker-osr/build b/test/570-checker-osr/build
deleted file mode 100644
index 10ffcc5..0000000
--- a/test/570-checker-osr/build
+++ /dev/null
@@ -1,20 +0,0 @@
-#!/bin/bash
-#
-# Copyright 2017 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-# See b/65168732
-export USE_D8=false
-
-./default-build "$@"