Revert "The dynamic services SDK produces a fat Mach binary of x64 and arm64 variants."

This reverts commit 3cf712d2305fcf2797aa4dd32bcf77eeb46a1905 in order to fix the build breakage: ".../obj/sky/services/dynamic/libFlutterServices.a and .../clang_x64/obj/sky/services/dynamic/libFlutterServices.a have the same architectures (x86_64) and can't be in the same fat output file"

engine/src/flutter/sky/tools/lipo.py

@@ -1,52 +0,0 @@
-#!/usr/bin/env python
-# Copyright 2015 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-import argparse
-import subprocess
-import sys
-import os
-
-
-def MakeStamp(stamp_path):
-  dir_name = os.path.dirname(stamp_path)
-
-  if not os.path.isdir(dir_name):
-    os.makedirs()
-
-  with open(stamp_path, 'a'):
-    os.utime(stamp_path, None)
-
-
-def main():
-  parser = argparse.ArgumentParser(
-      description='Creates a FAT Mach binary')
-
-  parser.add_argument('--path', action='append', dest='paths',
-      default=[], help='The path to a Mach binary')
-  parser.add_argument('--output', type=str)
-  parser.add_argument('--stamp', type=str)
-
-  args = parser.parse_args()
-
-  cmd = [
-    '/usr/bin/env',
-    'xcrun',
-    'lipo',
-  ]
-
-  cmd.extend(args.paths)
-
-  cmd.extend([
-    '-create',
-    '-output',
-    args.output,
-  ])
-
-  subprocess.check_call(cmd)
-
-  MakeStamp(args.stamp)
-
-if __name__ == '__main__':
-  sys.exit(main())