Open MPI missing MPI_COMM_DUP_FN and relatives for mpi_f08 bindings

[hppritcha]

It appears the the mpi_f08 bindings for MPI_Comm_dup_fn, etc. are missing. Looks like they
should be in attr-fn-f08-callback-interfaces.h.

[ggouaillardet]

i have some stuff ready for that, and I will pr tomorrow

[jsquyres]

This issue will be fixed by #623.