Add option to skip cpu feature and model verification in libvirt and rely on qemu 'enforce' option

[John Levon]

On Wed, Nov 23, 2022 at 01:59:54PM +0000, Daniel P. Berrangé wrote:

> The poster child example of QEMU evolving is the block layer
> which has many syntax versions

Sure, those sorts of things have indeed changed an awful lot, and libvirt
obviously brings value in that interface. But that feels IMHO quite different
from the CPU model/feature stuff. For one thing, it's unavoidable if you're
going to support multiple qemu versions.

>  https://www.qemu.org/docs/master/about/removed-features.html

The wholesale removal of Icelake-Client is the only salient example listed here,
right?  Given this is in libvirt too, how did libvirt help with this?

regards
john