X2APIC support

[sthaug at nethelp.no]

> > > Sorry, don't cleanly understund, what combination of BIOS setting I am need to probe?
> > > And what I am need to check?
> > 
> > Set 'Hyper-Threading' to Enabled.
> > Set 'X2APIC_OPT_OUT' to Enabled.
> > Try to boot.
> 
> Crashed at same point.

A comment about X2APIC, on a different type of system: I had to disable
X2APIC on HP ProLiant DL360 Gen9 servers in order to avoid 10.3-STABLE
crashing during boot.

Steinar Haug, Nethelp consulting, sthaug at nethelp.no