INT 21 - Novell NetWare v3.01+ shell interface - MULTIPLEXOR
        AH = F2h
        AL = function
            15h broadcast services (see AH=E1h"NetWare")
            17h connection control (see AH=E3h"NetWare")
        DS:SI -> request buffer
        ES:DI -> reply buffer
Return: AL = status
Notes:  this is a multiplexor to access other net interface functions which
          were accessed via a separate AH function in older versions
        the function number in AL is added to CCh to get the old function
          number which is desired