USB: cdc-acm: Adding second ACM channel support for Nokia N8

This adds the N8 to the list of devices in cdc-acm, in order to get the
secondary ACM device exposed.

In the spirit of:
http://kerneltrap.org/mailarchive/linux-usb/2010/9/4/6264554

Signed-off-by: Arvid Ephraim Picciani <arvid.picciani@nokia.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>