[llvm] [LLVM][rtsan] Add LLVM nosanitize_realtime attribute (PR #105447)

[Chris Apple via llvm-commits]

cjappl wrote:

Similarly unrelated build failure in CI:

```
_bk;t=1724336701213FAIL: lldb-shell :: Unwind/trap_frame_sym_ctx.test (1919 of 2590)

_bk;t=1724336701213******************** TEST 'lldb-shell :: Unwind/trap_frame_sym_ctx.test' FAILED ********************

_bk;t=1724336701214Exit Code: 1

_bk;t=1724336701214

_bk;t=1724336701214Command Output (stderr):


```

Some work being done on that now, based on this commit: https://github.com/llvm/llvm-project/commit/19d3f3417100dc99caa4394fbd26fc0c4702264e

https://github.com/llvm/llvm-project/pull/105447