This is possible since *of_device_id.data became const. While at it also
drop a cast to const that was never needed.

[ukl: split Arnd's patch by driver and add changlog]
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>