The viapm module build had what appear to be some debugging CFLAGS left
around to force the IO port to a fixed address. They were only turned
on in the module build and were present since the original import. This
breaks soft power-off on the Asus A7V since it reprograms the SMBus base
address to a different one than the BIOS expects. A similar issue was
found in the alpm(4) module build.

PR: kern/113986, i386/97468
MFC after: 3 days
Approved by: re