Verify serial/parallel port+IRQ against BIOS data area

[fragglet]

The BIOS data area contains the port addresses for COMx and LPTx plus flags for the number of serial and parallel ports. If using sersetup/parsetup, we should probably at the very least sanity check against these values and print a warning if they don't match what we're trying to use

https://stanislavs.org/helppc/bios_data_area.html