[PATCH] USBATM: change the default speedtouch iso altsetting
The maximum possible bandwidth for a speedtouch modem is about 7Mbaud.
You can only get this by using isochronous urbs (enable_isoc=1) and
altsetting 3. With the current default altsetting of 2, the modem
maxes out at about 4Mbaud. So change the default altsetting to 3
when using isochronous urbs. It would be nice to base the altsetting
on the detected line speed, but that's hard given the current design.