Staging: ccg: remove it from the build

This driver has been nothing but trouble, and no one shipping a new
Android device uses it, so let's just drop it, making the USB Gadget
driver authors lives a whole lot easier as they do their rework.

Cc: John Stultz <john.stultz@linaro.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>