[compiler-rt] [asan] Add experimental 'track_poison' flag (PR #133175)

[Vitaly Buka via llvm-commits]

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@@ -10,15 +10,64 @@
 //
 // Shadow memory poisoning by ASan RTL and by user application.
 //===----------------------------------------------------------------------===//
+#ifndef ASAN_POISONING_H
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vitalybuka wrote:

please land this fix in a separate patch

https://github.com/llvm/llvm-project/pull/133175