net/openmpi: upgrade to v5.0.1

Release notes available at
https://www-lb.open-mpi.org/software/ompi/major-changes.php.

Notes:

• The MPI C++ bindings were deprecated in the MPI-2.2 standard in 2009, and removed from the MPI-3.0 standard in 2012. The MPI C++ bindings were then removed from Open MPI v5.0.0 in 2022;

• ofi (libfabric) was explicitly disabled in this port - I don’t know why but kept it this way;

• ROMIO has been disabled (See https://github.com/open-mpi/ompi/issues/9715);

• 32 bits platforms are not supported: this port has been repocopied to net/openmpi4 for them.