INT 17 - Alloy MW386 v2+ - GET/SET SPOOL FLAGS
        AH = A7h
        AL = spool flags
            bit 0: banner page enabled (see AH=A4h)
                1: form feed enabled (see AH=A6h)
                2-6: reserved (0)
                7: set flags if 1, get flags if 0
        BX = logical device number
            00h-03h = LPT1-LPT4
            04h-07h = COM1-COM4
Return: AL = status (see AH=81h)
Note:   the documentation does not state which register contains the result of
          a GET
SeeAlso: AH=A6h