Re: Add spin_delay() implementation for Arm in s_lock.h

As promised, here is the remaining data:

1 worker, w/o patch: 5236 ms +/- 252ms
1 worker, w/   patch: 5529 ms +/- 168ms

2 worker, w/o patch: 4917 ms +/- 180ms
2 worker, w/   patch: 4745 ms +/- 169ms

4 worker, w/o patch: 6564 ms +/- 336ms
4 worker, w/   patch: 6105 ms +/- 177ms

8 worker, w/o patch: 9575 ms +/- 2375ms
8 worker, w/   patch: 8115 ms +/- 391ms

16 worker, w/o patch: 19367 ms +/- 3543ms
16 worker, w/   patch: 18004 ms +/- 3701ms

32 worker, w/o patch: 101509 ms +/- 22651ms
32 worker, w/   patch: 104234 ms +/- 26821ms

48 worker, w/o patch: 243329 ms +/- 70037ms
48 worker, w/   patch: 189965 ms +/- 79459ms

64 worker, w/o patch: 552443 ms +/- 22841ms
64 worker, w/   patch: 502727 ms +/- 45253ms

From this data, on average the patch is beneficial at high worker (CPU) counts tested: 48, 63.  At 32 and below the
performanceis relatively close to each other.  
 

Thanks,
Geoff