[llvm] [asan] Ensure __asan_register_elf_globals is called in COMDAT asan.module_ctor (PR #67745)

[Fangrui Song via llvm-commits]

MaskRay wrote:

> [lab.llvm.org/buildbot/#/builders/168](https://lab.llvm.org/buildbot/#/builders/168) ?

Reverted. Edited the description about the issue:

> If the unique module ID is empty, don't call SetComdatForGlobalMetadata (placing `@.str` in a COMDAT would incorrectly discard internal `@.str` in other compile units)

https://github.com/llvm/llvm-project/pull/67745