[llvm] IRVerifier: Allow GlobalValue as llvm.threadlocal.address operand (PR #88321)

[Matthias Braun via llvm-commits]

MatzeB wrote:

This amends #87841 : I just noticed in the class hierarchy and reading the language spec that `GlobalAlias` and `GlobalVariable` can be thread local. So it is best to allow any `GlobalValue` in the check I added the other day.

FWIW the X86 backend seems to produce invalid code that isn't actually doing thread-local accesses in this case, but that is probably just a bug for a (unused?) feature.

https://github.com/llvm/llvm-project/pull/88321