[llvm] [llvm-ml] Remove unsafe getCurrentSegmentOnly() call (PR #123355)

[Eric Astor via llvm-commits]

ericastor wrote:

I can try to minimize the issue & convert it into a test, but I'm not quite clear on what circumstances actually provoke it. For example, neither db48f1a1764023f8efeb055e343b967d1eb37d19 nor 626eef5ecf92e98cbfccfa6134e0a760e7592813 seemed to include a test to verify that their changes were separately safe?

https://github.com/llvm/llvm-project/pull/123355