Input: implement managed polled input devices

Managed resources are becoming more and more popular in drivers. Let's
implement managed polled input devices, to complement managed regular input
devices.

Similarly to managed regular input devices only one new call
devm_input_allocate_polled_device() is added and the rest of APIs is
modified to work with both managed and non-managed devices.

Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Tested-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>