bench speed r0

> ./benchmark_speed.py --builddir build --target-module run_native
Warning: qrduino executable not found.
Traceback (most recent call last):
  File "./benchmark_speed.py", line 388, in <module>
    sys.exit(main())
  File "./benchmark_speed.py", line 367, in main
    raw_data, rel_data = collect_data(benchmarks, remnant)
  File "./benchmark_speed.py", line 285, in collect_data
    raw_data[bench] = benchmark_speed(bench, target_args)
  File "./benchmark_speed.py", line 224, in benchmark_speed
    for arg in arglist:
UnboundLocalError: local variable 'arglist' referenced before assignment