the arm to compile without all the extras that don't appear, at least
not in the flavors of ARM I deal with. This helps us save about 100k.
If I've botched the available devices on a platform, please let me
know and I'll correct ASAP.
'device mem' over from GENERIC to DEFAULTS to be consistent with i386 and
amd64. Additionally, on ia64 enable ACPI by default since ia64 requires
acpi.