Bug#1058876: libopenmpi-dev: paths missing /usr/include...(for fortran mpi.mod)

[Drew Parsons]

reopen 1058876
block 1058944 by 1058876
thanks

Alas, the fix in openmpi 4.1.6-3 for the include path to the openmpi 
fortran modules has hardcoded x86_64-linux-gnu

This is preventing builds and tests on other architectures, e.g. 
rebuilding sundials for the petsc transition.

I think openmpi's debian/tests will also need Depends: pkg-config for 
the new compile_run_cc_pkgconfig test.