Fix error in custom call registration for some FFI functions
We are getting the following errors:
```
Duplicate FFI handler registration for cu_threefry2x32_ffi on a platform CUDA
Duplicate FFI handler registration for cu_lu_pivots_to_permutation on a platform CUDA
```
It seems that with the ffi registration mechanism based on `XLA_FFI_REGISTER_HANDLER` it is not possible anymore to
register a call target twice.
The fix here is to rollback the changes in https://github.com/google/jax/pull/22178
and disable the changes from https://github.com/google/jax/pull/20997.
PiperOrigin-RevId: 647993991
