cmake HAVE_ISO_FORTRAN_ENV examples

HDFGroup/hdf5 config/HDF5UseFortran.cmake :129 

check_fortran_source_compiles (${SOURCE_CODE} HAVE_ISO_FORTRAN_ENV SRC_EXT f90)

InsightSoftwareConsortium/ITK Modules/ThirdParty/HDF5/src/itkhdf5/config/cmake/HDF5UseFortran.cmake :111 

check_fortran_source_compiles (${SOURCE_CODE} HAVE_ISO_FORTRAN_ENV SRC_EXT f90)