Spack receipe for PDI should depend on python when Fortran is enabled

[tpadioleau]

I noticed that BUILD_FORTRAN requires Python

https://github.com/pdidev/pdi/blob/1e8c1bb6e6cc11ec0e509db74fb57315cee4653a/CMakeLists.txt#L218-L220

I was wondering if this was really necessary ? Because it fails on my system.

[jbigot]

Yep, FORTRAN requires zpp that in turn requires python. Maybe we could skip this here because it should be looked for in the add_subdirectory, but it shouldn't hurt either.

[tpadioleau]

Ok thanks, then I guess one should update the Spack package https://github.com/spack/spack-packages/blob/develop/repos/spack_repo/builtin/packages/pdi/package.py ? The variant +fortran does not require python.

[jbigot]

good catch