Add partitioned communication APIs to TKR mpi module

[jsquyres]

Per #9543 (review), the MPI 4.0 partitioned communication APIs are missing from the TKR mpi module implementation (i.e., ompi/mpi/fortran/use-mpi-tkr).

The TKR implementation is for older Fortran compilers, but it's still supported, and therefore needs to have these APIs added.

Note that we don't declare subroutines in the TKR interface that accept choice buffers (e.g., don't add prototypes for MPI_PSEND_INIT and MPI_PRECV_INIT), but there's still several subroutines that should be prototyped in the TKR mpi module (e.g., MPI_PREADY, MPI_PARRIVED, etc.).

This should hopefully be a pretty easy / quick task. I'm tentatively assigning it to @mdosanjh since he submitted the original partitioned communication code.

[mdosanjh]

I can take a look at this today.

[mdosanjh]

@jsquyres One thing I'm not 100% clear on here is the 'choice buffers'; I'm assuming that MPI_Pready_list should not have a prototype here as it includes a buffer of partitions to mark ready?

[jsquyres]

@mdosanjh No, the array_of_partitions argument is an array of integers, so that should be fine. The "choice buffers" we have problems with in the TKR mpi module are completely arbitrary buffers (e.g., the buffer arguments to MPI_SEND and MPI_RECV).

[awlauria]

I believe this can be closed as #9593 was merged into v5, which included #9585 as a cherry-pick. If I am wrong, please re-open.