move section variable to within #ifdef WIN32 block that uses it, that
var remains unused otherwise.
isapnp cleanup
parallel port emulation: skip registering I/O write handler for the
status port (port 0x379, 0x279, etc.). This port is normally read only,
which is why the ISA PnP standard later abuses it to offer the write end
of the address selection in the PnP protocol. This fix allows PnP
enumeration to work properly.