removed remains from the ccg driver

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
removed duplicate ITG3200 driver in staging/iio

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
coding style cleanup

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>