[clang] [compiler-rt] [llvm] [tsan] Revive TSAN's standalone deadlock sanitizer implementation (PR #212748)

[Vitaly Buka via cfe-commits]

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vitalybuka wrote:

but after that it would be nice to have PR which test only LLVM part of new mode, IR tests with instrumentation you expect.

https://github.com/llvm/llvm-project/pull/212748