Serial port stops working after upgrade to 9-CURRENT

[Ian Lepore]

On Fri, 2012-01-20 at 07:28 -0800, Jeremy Chadwick wrote:
> Also, does this machine have ACPI support?  I do not use 9.x, but uartX
> on our RELENG_8 systems is tied to acpi0, not isa0.  It's been this way
> for quite some time (even our RELENG_7 boxes are this way).

It works on systems that don't have acpi, or have it disabled, as well.
It seems that all the legacy isa devices are parented to both the acpi
and isa busses, and some magic I don't understand makes the acpi bus
take precedence over isa when it's available.

-- Ian