Upgrade to version 3.20170511.1 to fix Skylake broken hyper-threading

[Adrien Beau]

As reported by Henrique de Moraes Holschuh from Debian, there is a hyperthreading-related bug in recent Skylake and Kaby Lake processors that can, when triggered, cause unpredictable system
behavior (application and system misbehavior, data corruption and data loss in the worst case).

For Skylake processors, this bug is fixed by the microcode included in version 3.20170511.1, available on Arty, but not backported on previous releases still under support (notably on Xenial, the current LTS).

Please backport intel-microcode 3.20170511.1 on Zesty, Yakkety, Xenial and Trusty, if possible.

As a workaround, using the package from Arty reportedly works fine.

Sources:
- Debian Advisory: https://lists.debian.org/debian-devel/2017/06/msg00308.html

(And to conform to the guidelines: I am using Xenial, have an affected CPU with microcode 0xA6, have package version 3.20151106.1, and expect to have microcode 0xBA.)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Dimitri John Ledkov (xnox)]

This is a duplicate.