[tsan] Intercept __tls_get_addr_earlier

This can be useful because dlsym() may call malloc on failure which could
result in other interposed functions being called that could eventually
make use of TLS. While the crash that I experienced originally has been
fixed differently (by not using global-dynamic TLS accesses in the mutex
deadlock detector, see https://github.com/llvm/llvm-project/pull/83890),
moving this interception earlier is still a good since it makes the code
a bit more robust against initialization order problems.

Reviewed By: MaskRay, vitalybuka

Pull Request: https://github.com/llvm/llvm-project/pull/83886