Input: i8042 - fix modpost warning

i8042_unregister_ports's only caller i8042_remove is a __devexit function
so make it __devexit too.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>