[llvm] [llvm][lit] Add tsan feature when enabled (PR #94573)

[Alexander Richardson via llvm-commits]

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@@ -131,6 +131,8 @@ def __init__(self, lit_config, config):
             features.add("msan")
         if "undefined" in sanitizers:
             features.add("ubsan")
+        if "thread" in sanitizers:
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arichardson wrote:

Agreed that it doesn't make sense to rename just one of them. And 200 is quite a bit of churn so I'm fine just keeping them as is.

https://github.com/llvm/llvm-project/pull/94573