Input: remove use of __devinit

CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Javier Martinez Canillas <javier@dowhile0.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>