[9fans] usb/serial control open

[erik quanstrom]

it seems odd to me that opening the ctl file would
reset some serial parameters.  wouldn't it be better
to leave them alone?

static int
dopen(Usbfs *fs, Fid *fid, int)
{
        ulong path;
        Serialport *p;

        path = fid->qid.path & ~fs->qid;
        p = fs->aux;
        switch(path){           /* BUG: unneeded? */
        case Qdata:
                dsprint(2, "serial, opened data\n");
                break;
        case Qctl:
                dsprint(2, "serial, opened ctl\n");
                if(p->isjtag)
                        return 0;
>>              serialctl(p, "l8 i1");  /* default line parameters */
                break;
        }
        return 0;
}

- erik