[lld] [lld] Add target support for SystemZ (s390x) (PR #75643)

[Fangrui Song via llvm-commits]

MaskRay wrote:

Thanks for the updated. The tests are very thorough now! After simplifying `// Like other platforms, calls to the TLS helper routine on SystemZ carry` with my suggestion I think this is good to go.


https://github.com/llvm/llvm-project/pull/75643