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

[Vitaly Buka via cfe-commits]

================
@@ -79,6 +79,9 @@ SANITIZER("type", Type)
 // ThreadSanitizer
 SANITIZER("thread", Thread)
 
+// DeadlockSanitizer (ThreadSanitizer, with only the deadlock detection.)
----------------
vitalybuka wrote:

we need documentation somewhere

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