th specific device address.
==============================================================================

_Description_
     This function returns the host address that has been mapped to the
     device address specified by D.

_C/C++_:
     _Prototype_:   'void *acc_hostptr(d_void *d);'

_Reference_:
     OpenACC specification v2.6 (https://www.openacc.org), section
     3.2.29.