Fortuna: Add failpoints to simulate initial seeding conditions
Set debug.fail_point.random_fortuna_pre_read=return(1) and
debug.fail_point.random_fortuna_seeded=return(1) to return to unseeded
status (sort of). See the Differential URL for more detail.
The goal is to reproduce e.g. Lev's recent CURRENT report about failing
newfs arc4random(3) usage (fixed in r338542).
No functional change when failpoints are not set.
Reported by: lev
Reviewed by: delphij, markm
Approved by: secteam (delphij)
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D17047
(cherry picked from commit 9b8d0fe462b2f3f689cb87fe34bd42c388e23d49)