[llvm] [runtimes] Skip custom linker validation for gpu/offload targets (PR #189933)

[Petr Hosek via llvm-commits]

https://github.com/petrhosek approved this pull request.

Ideally we wouldn't be using `llvm/cmake/modules/HandleLLVMOptions.cmake` for runtimes at all but that's going to require some non-trivial work.

https://github.com/llvm/llvm-project/pull/189933