HID: Create a generic device group

Devices that do not have a special driver are handled by the generic
driver. This patch does the same thing using device groups; Instead of
forcing a particular driver, the appropriate driver is picked up by
udev. As a consequence, one can now move a device from generic to
specific handling by a simple rebind. By adding a new device id to the
generic driver, the same thing can be done in reverse.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Acked-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>