[pve-devel] qemu-server : add support for ovmf efi roms

[Alexandre Derumier]

This patch add support for ovmf efi roms, with a new option "ovmf:1"

users have reported problem with vga pcie passthrough with proxmox 4.
https://forum.proxmox.com/threads/24362-PCIe-passthrough-does-not-work

and ovmf fix the problem with uefi roms.

Here a good wiki on archlinux:

https://wiki.archlinux.org/index.php/PCI_passthrough_via_OVMF