- it is now possible to include the selected mpi version in the
top-level bashrc or prefs.sh file. For example,
WM_MPLIB=OPENMPI-4.1.1 or WM_MPLIB=openmpi-4.1.1
after evaluation of the config.sh/mpi, this will define
WM_MPLIB=OPENMPI-4.1.1 and FOAM_MPI=openmpi-4.1.1
During the wmake, the mpi-rules will first load the MPI 'family'
rules (OPENMPI in this example) before trying to load
version-specific rules if they exist.
NOTE: the regular user-defined prefs system is unaffected by this
change. This means it is still possible to use a file such as
'prefs.openmpi' to define the preferred version instead or as well.
However, it does mean inconsistent naming can be specified.
For example, specify WM_MPLIB=OPENMPI-4.1.1 at the top-level but
actually have FOAM_MPI=openmpi-4.0.6 in the prefs.openmpi file.
This will make the value of WM_MPLIB misleading.
CONFIG: foamConfigurePaths support for sys-openmpi major version
CONFIG: cleanup any shadow env variables