[pve-devel] qemu-server : qemu cpu flags optimisations for kernel 3.10

[Alexandre Derumier]

This patch series enabled new cpuflags optimisations 
witch need kernel 3.10 and was not enabled before.

To avoid breakage with live migration && snapshot restore,
I have introduce a new check to enable only theses cpu flags
if qemu version or machine option >= 2.3.
(As I think that proxmox 4.0 will be qemu 2.3, it should be ok)

This is candidate for master branch, proxmox 4.0