INT 21 - LANtastic - CONTROL QUEUE
        AX = 5FA2h
        BL = control command
            00h start despooling (privileged)
            01h halt despooling (privileged)
            02h halt despooling at end of job (privileged)
            03h pause despooler at end of job (privileged)
            04h print single job (privileged)
            05h restart current job (privileged)
            06h cancel the current job
            07h hold queue entry
            08h release a held queue entry
            09h make queue entry a rushed job (privileged)
        CX:DX = sequence number to control (commands 06h-09h)
        DX = physical printer number (commands 00h-05h)
            00h-02h LPT1-LPT3
            03h,04h COM1,COM2
            other       all printers
        ES:DI -> ASCIZ server name in form "\\machine"
Return: CF clear if successful
        CF set on error
            AX = error code