[SeaBIOS] [PATCH] don't expose pvpanic device in the UI

[Paolo Bonzini]

> Libvirt has no problem enabling -device pvpanic for all guests where
> <on_crash> is set to a non-default value, since the use of <on_crash> is
> a sufficient hint that the user expects the guest to be able to notify
> of a crash in the first place.  But I definitely agree that it is more
> conservative to ask libvirt to always provide -device pvpanic than it is
> to blindly enable the device and hope that it never causes damage.

Changing guest ABI depending on <on_crash> is a much much worse
cure than the disease.

Paolo