MPI info object

[Wei-keng Liao]

The MPI info object passed into ncmpi_open() and ncmpi_create() should be
duplicated using
      MPI_Info_dup(info, &nciop->mpiinfo);
instead of
      nciop->mpiinfo = info;
in ncmpiio_create() and ncmpiio_open() in file mpincio.c.

The same info object will be used in MPI_file_setview() later in the data 
mode APIs. The above fix can prevent from freeing the info object by
applications before the data mode APIs are called.

Wei-keng