Audit random seed

See the pkg-sysvinit-devel archives, in July and August 2010, for an interesting discussion about random seeds unicity, especially at early boot time.

We should audit such matters in Tails.

Blueprint: https://tails.boum.org/blueprint/randomness_seeding/

Related issues

• Related to #7102
• Related to #5650 (closed)
• Related to #7642 (closed)
• Related to #7646 (closed)
• Related to #7675 (closed)

Original created by @tails on 6116 (Redmine)