[compiler-rt] Revert "[scudo] Use getMonotonicTimeFast for tryLock." (PR #86590)

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ChiaHungDuan wrote:

> We could also continue to use this function if we did a right shift to get better resolution.
> 
> However, I'm not sure that using a random seed here make a lot of sense. It almost might be better to just use a round-robin especially when there are only two TSDs.
> 
> But that requires more experimentation.

In this case, for example, `getMonotonicTimeFast()` in the interval of 0~4 ms returns the same value, so the shifting still gives the same value. I did some experiments with different strategies, it has very small improvements but I think it's still worth of adopting new algorithm. 

https://github.com/llvm/llvm-project/pull/86590