qemu: Always add serial= for disks
This is used for device enumeration order, and is required for NVMe
drives apparently.  Hit this while trying to use a NVMe device as
a target for coreos-install testing (not primary disk).
@@ -403,6 +403,9 @@ func (builder *QemuBuilder) addDiskImpl(disk *Disk, primary bool) error {
diskOpts := disk.DeviceOpts
if primary {
diskOpts = append(diskOpts, "serial=primary-disk")
+ } else {
+ // Note that diskId is incremented by addQcow2DiskFd
+ diskOpts = append(diskOpts, "serial="+fmt.Sprintf("disk%d", builder.diskId))
}
channel := disk.Channel
if channel == "" {
