Anaconda tries to be helpful by detecting altix systems and using the proper
serial console (ttySG0) automatically.

Unfortunately, SGI has graphics workstations now that are like Altix systems
with graphics.  Customers with these systems probalby don't have serial consoles
attached.  

Jeremy is swamped right now and probably isn't ready to think about this.
I was worried we'd forget about it.  I'm assigning this bug to me for now.
When the installer has settled down in fedora development, I'll re-assign
if it's still a problem.