Bug#963525: Steam is currently broken in sid + Workaround

[Ungoliant]

Hello team!

I want to confirm the issue reported by Reiner Herrmann <reiner at reiner-h.de>
in the previous email of this thread.

More detail on how it got broken:

I suffered the same problem after updating my system. As Reiner reported,
the error seems to be related to crypto libraries.

I investigated and my last update installed the following crypto libraries:
- libargon2-1:i386
- libcryptsetup12:i386
Those libraries seem to be pulled by a the new version of libmount1:i386

Workaround:
- Revert libmount1:i386 and uninstall libargon2-1:i386 and
libcryptsetup12:i386
After that, steam will work.