mpi/forran: Support MPI_IN_PLACE on (I)ALLTOALLW and (I)EXSCAN

`MPI_IN_PLACE` support for `MPI_ALLTOALLW` and `MPI_EXSCAN` was
added in MPI-2.2 but it was missed in OMPI Fortran binding code.

Author: kawashima-fj

ompi/mpi/fortran/mpif-h/alltoallw_f.c

@@ -98,7 +98,7 @@ void ompi_alltoallw_f(char *sendbuf, MPI_Fint *sendcounts,
         --size;
     }
 
-    /* Alltoallw does not support MPI_IN_PLACE */
+    sendbuf = (char *) OMPI_F2C_IN_PLACE(sendbuf);
     sendbuf = (char *) OMPI_F2C_BOTTOM(sendbuf);
     recvbuf = (char *) OMPI_F2C_BOTTOM(recvbuf);
 

ompi/mpi/fortran/mpif-h/exscan_f.c

@@ -80,7 +80,7 @@ void ompi_exscan_f(char *sendbuf, char *recvbuf, MPI_Fint *count,
     c_type = PMPI_Type_f2c(*datatype);
     c_op = PMPI_Op_f2c(*op);
 
-    /* MPI_IN_PLACE is not supported */
+    sendbuf = (char *) OMPI_F2C_IN_PLACE(sendbuf);
     sendbuf = (char *) OMPI_F2C_BOTTOM (sendbuf);
     recvbuf = (char *) OMPI_F2C_BOTTOM (recvbuf);
 

ompi/mpi/fortran/mpif-h/ialltoallw_f.c

@@ -99,7 +99,7 @@ void ompi_ialltoallw_f(char *sendbuf, MPI_Fint *sendcounts,
         --size;
     }
 
-    /* Ialltoallw does not support MPI_IN_PLACE */
+    sendbuf = (char *) OMPI_F2C_IN_PLACE(sendbuf);
     sendbuf = (char *) OMPI_F2C_BOTTOM(sendbuf);
     recvbuf = (char *) OMPI_F2C_BOTTOM(recvbuf);
 

ompi/mpi/fortran/mpif-h/iexscan_f.c

@@ -81,7 +81,7 @@ void ompi_iexscan_f(char *sendbuf, char *recvbuf, MPI_Fint *count,
     c_type = PMPI_Type_f2c(*datatype);
     c_op = PMPI_Op_f2c(*op);
 
-    /* MPI_IN_PLACE is not supported */
+    sendbuf = (char *) OMPI_F2C_IN_PLACE(sendbuf);
     sendbuf = (char *) OMPI_F2C_BOTTOM (sendbuf);
     recvbuf = (char *) OMPI_F2C_BOTTOM (recvbuf);