[Qemu-ppc] Qemu boot device precedence over nvram boot-device setting

[Avik Sil]

Hi,

We would like to get a method to boot from devices provided in -boot 
arguments in qemu when the 'boot-device' is set in nvram for pseries 
machine. I mean the boot device specified in -boot should get a 
precedence over the 'boot-device' specified in nvram.

At the same time, when -boot is not provided, i.e., the default boot 
order "cad" is present, the device specified in nvram 'boot-device' 
should get precedence if it is set.

What should be the elegant way to implement this requirement? 
Suggestions welcome.

Regards,
Avik