INT 21 - LANtastic v3+ - CREATE INDIRECT FILE
        AX = 5FB4h
        DS:SI -> 128-byte buffer containing ASCIZ contents of indirect file
        ES:DI -> full ASCIZ path of indirect file to create, incl machine name
Return: CF clear if successful
        CF set on error
            AX = error code
Note:   the contents of the indirect file may be any valid server-relative path