Fri Aug 9 08:48:35 EDT 2013

Additional interfaces

As suggested by Peter Stuge, add a second interface to the USB device.

This allows the default endpoint to be used to create a side channel
for the phone APDU traffic and communication control.

A recap:
- USBDeviceDescriptor.bNumConfigurations = 1

- CCIDDriverConfigurationDescriptors contains all descriptors returned
  for a GET_CONFIGURATION request.

In the at91lib code, interfaces are added in cciddriver.c :