===================================================================

_Description_
     This function updates a pointer on the device from pointing to a
     device-pointer address to pointing to the corresponding host data.

_C/C++_:
     _Prototype_:   'acc_detach(h_void **ptr);'
     _Prototype_:   'acc_detach_async(h_void **ptr, int async);'
     _Prototype_:   'acc_detach_finalize(h_void **ptr);'
     _Prototype_:   'acc_detach_finalize_async(h_void **ptr, int async);'

_Reference_:
     OpenACC specification v2.6 (https://www.openacc.org), section
     3.2.35.