jenkins 1.537.
git-etc: remove all code.

I've given up on this; too many edge cases.
If someone else wants to pick it up then send me a message and I'll walk
you through the approach.
Add Hardware::CPU.ssse3? helper method.

Closes #23796.

Signed-off-by: Misty De Meo <mistydemeo@gmail.com>
Hardware::CPU: add extmodel helper