Add missing argument name.

Signed-off-by: Juan M. Bello-Rivas <jbellorivas@rigetti.com>

ompi/include/mpi.h.in

@@ -2250,7 +2250,7 @@ OMPI_DECLSPEC  int PMPI_Reduce(const void *sendbuf, void *recvbuf, int count,
 OMPI_DECLSPEC  int PMPI_Ireduce(const void *sendbuf, void *recvbuf, int count,
                                MPI_Datatype datatype, MPI_Op op, int root, MPI_Comm comm, MPI_Request *request);
 OMPI_DECLSPEC  int PMPI_Reduce_local(const void *inbuf, void *inoutbuf, int count,
-                                     MPI_Datatype datatype, MPI_Op);
+                                     MPI_Datatype datatype, MPI_Op op);
 OMPI_DECLSPEC  int PMPI_Reduce_scatter(const void *sendbuf, void *recvbuf, const int recvcounts[],
                                        MPI_Datatype datatype, MPI_Op op, MPI_Comm comm);
 OMPI_DECLSPEC  int PMPI_Ireduce_scatter(const void *sendbuf, void *recvbuf, const int recvcounts[],