gn2bp: remove output comparison and --check_only support

This does not currently work and is not needed at the moment.

Test: n/a
Change-Id: I23f18e553dfbc6e626e8d4a29e3ffcf137ba2180
diff --git a/tools/gn2bp/gen_android_bp b/tools/gn2bp/gen_android_bp
index 8d86111..b7e2e6b 100755
--- a/tools/gn2bp/gen_android_bp
+++ b/tools/gn2bp/gen_android_bp
@@ -1035,10 +1035,6 @@
   parser = argparse.ArgumentParser(
       description='Generate Android.bp from a GN description.')
   parser.add_argument(
-      '--check-only',
-      help='Don\'t keep the generated files',
-      action='store_true')
-  parser.add_argument(
       '--desc',
       help='GN description (e.g., gn desc out --format=json --all-toolchains "//*"'
   )
@@ -1117,8 +1113,7 @@
   out_files.append(os.path.join(buildflags_dir, 'perfetto_build_flags.h.swp'))
   gn_utils.gen_buildflags(gn_args, out_files[-1])
 
-  # Either check the contents or move the files to their final destination.
-  return gn_utils.check_or_commit_generated_files(out_files, args.check_only)
+  return 0
 
 
 if __name__ == '__main__':