[libunwind] [Libunwind] Don't XFAIL tests with msan (PR #120013)

[Dmitry Chestnykh via cfe-commits]

chestnykh wrote:

@ldionne i run these tests locally with msan (x86-64) and have no errors. Could you please tell on what architecture(s) the tests was failing?  

https://github.com/llvm/llvm-project/pull/120013