Bug#1120424: pmix: tests fail due to default foreign tool support

[Drew Parsons]

Package: libpmix-dev
Version: 6.0.0+really5.0.9-2
Followup-For: Bug #1120424

Unfortunately the patch in 6.0.0+really5.0.9-2 does not alone resolve
the problem. ptscotch still fails in lo chroot. Upstream is looking
into it further (says it's probably a separate issue that can be
controlled via mpirun parameters)

The same error can also be seen in builds of mumps,
https://buildd.debian.org/status/fetch.php?pkg=mumps&arch=arm64&ver=5.8.1-1exp1&stamp=1762774445&raw=0

=== running 64-bit c_example (MPI) ===
--------------------------------------------------------------------------
You requested support for remote tool connections, but no non-loopback
interfaces were found after applying any include or exclude directives:

  Include:    NULL
  Exclude:    NULL
  Available:  lo

Please adjust your include or exclude to allow selection of a
non-loopback interface.
--------------------------------------------------------------------------

(64-bit is an additional complication here to be aware of, but it was
previously passing with pmix 5.0.8)

Likewise hypre is failing build,
https://buildd.debian.org/status/fetch.php?pkg=hypre&arch=s390x&ver=2.33.0-1exp1&stamp=1762773797&raw=0
although it is not reporting the full error message.
I suspect it's the same problem.