Input: i8042 - add missing include

<linux/i8042.h> include uses ENODEV when included with
!IS_ENABLED(CONFIG_SERIO_I8042) and so need to include it.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Link: https://lore.kernel.org/r/49fd4d400d1ab62095e5ed75a6637f883c0d071b.1682795105.git.mirq-linux@rere.qmqm.pl


Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>