This reverts commit 6b7c1815e1.
The attempted fix has been reported to cause high CPU usage after
backup [0]. Not difficult to reproduce and it's iothreads getting
stuck in a loop. Downgrading to pve-qemu-kvm=8.1.2-4 helps which was
also verified by Christian, thanks! The issue this was supposed to fix
is much rarer, so revert for now, while upstream is still working on a
proper fix.
[0]: https://forum.proxmox.com/threads/138140/
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>