enabled in hid-core, but _is_ used when DEBUG is also enabled in hid-input.
       Mark the function with __attribute__((unused)) to silence the warning
       when only hid-core is being DEBUGged.
Signed-off-by: Adam Kropelin <akropel1@rochester.rr.com>
Signed-off-by: Vojtech Pavlik <vojtech@suse.cz>