The driver core clears the driver data to NULL after device_release or on
probe failure. Thus, it is not needed to manually clear the device driver
data to NULL.
Signed-off-by: Jingoo Han <jg1.han@samsung.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>