Disk format parameter is ignored

[pupaxxo]

In config_qemu format disk parameter is ignored and not sent:

https://github.com/Telmate/proxmox-api-go/blob/master/proxmox/config_qemu.go#L1088

	// Keys that are not used as real/direct conf.
	ignoredKeys := []string{"key", "slot", "type", "storage", "file", "size", "cache", "volume", "container", "vm", "mountoptions", "storage_type", "format"}

	// Rest of config.
	diskConfParam = diskConfParam.createDeviceParam(disk, ignoredKeys)

I'm using packer to create vms and disks are created only in raw format.

Why is it ignored? Is it a bug/typo?