Meltdown and Spectre information update

[Hleb Valoshka]

On 1/7/18, Matthew Dillon <dillon at backplane.com> wrote:

> The Meltdown protection is now stable in the master branch.  A number of
> minor bugs were fixed after the initial commit.  I am looking into possibly
> getting into -stable but I don't know yet.

Phoronix's benchmarks show quite large performance drop:

https://www.phoronix.com/scan.php?page=article&item=dragonfly-bsd-meltdown&num=2