[bhyve][arm64] Number of allowed vcpus

[Peter Grehan]

Hi Andrei,

> I've summed up your proposals and sketched and algorithm:
> N - the number of vcpus from the '-c' parameter
> X - the number of vcpus from the device tree
> 
> if there isn't the parameter -> start the vm with X vcpus
> if there is the parameter --> if N <= X -> start the vm with N parameters
>                                         |-> if N > X -> throw an error
> 
> I believe this gives the opportunity to rebuild the device tree and use all
> vcpus (first branch)
> or let the device tree as it is (more vcpus) but use only a subset of them.
> Is this alright?

  If you are going to have the ability to rebuild the device tree, you 
might as well do it every time.

  If a user hasn't specified how many vCPUs on the command line, it's 
safe to assume a default of 1.

later,

Peter.