Add PnetCDF module for Betzy settings.

[TomasTorsvik]

Would it be possible to add a PnetCDF module for Betzy? BLOM breaks when setting IOTYPE=1 (use pnetcdf), it would be nice if this could be fixed. I tested the 1.12.1-iompi-2020a version, that seems to work.

[monsieuralok]

Hi Tomas,
Good day, it seems to work but, it is not setting stripe count automatically. Therefore, we have removed it.

[TomasTorsvik]

Hi @monsieuralok ,
thanks for getting back to me about this. I'm not familiar with the inner workings of PnetCDF, and how it interacts with MPI and the file system. I don't think I need the pnetcdf functionality at the moment, but I am concerned about having "dead" code (i.e. code that is never tested) in the code base. Is pnetcdf used on other systems than Betzy, or is it not used at all? Is there a prospect that the stripe count issue can be fixed at some point?