Removing the Linux /dev/random blocking pool

They're still mixing more entropy in, even if the kernel no longer bothers to block reads if there is insufficient entropy (after initialization). (AIUI, it can still block *additions* of entropy when there *is* believed to be sufficient entropy in the pool, so things like the chaoskey don't needlessly eat CPU time throwing entropy into the pool when it already probably has lots and nobody's using any of it.)