message: examples: Use public Fortran adios2_init signature
  The example was calling `adios2_init_config` which is a private name
  implementing one variant of the `adios2_init` generic procedure.
  Use the public name instead just as applications should.
diff: @@ -51,7 +51,7 @@ program helloInsituMPIWriter
  count_dims = (/ ndx, ndy /)
  ! Create adios handler passing the communicator, config file, debug mode and error flag
  - call adios2_init_config(adios, xmlfile, comm, adios2_debug_mode_on, ierr)
  + call adios2_init(adios, xmlfile, comm, adios2_debug_mode_on, ierr)
  ! Declare an IO process configuration inside adios,
  ! Engine choice and parameters for 'writer' come from the config file
  