fix: Update BrainScaleS software to include (more) missing includes

This includes (hopefully) all missing headers…

changed target branch from spack-v0.20.0 to master

added 8 commits

• 6a40c18a...4b686e31 - 7 commits from branch master
• a7a45fed - fix: Update BrainScaleS software to include (more) missing includes

Compare with previous version

mentioned in merge request !360 (closed)

@emuller there are still some errors (but I think those were fixed already in 0.6-a1..? misplaced tag maybe?)

Jap, I forgot the workaround for this gcc@10.3 ambiguity problem (which hasdn't been through our CR) :/ — updated and retriggered.

mentioned in commit ae996139

merged