Input: adp5588-keys - switch to using managed resources

This simplifies error handling in probe() and reduces amount of explicit
code in remove().

Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Link: https://lore.kernel.org/r/20220528045631.289821-3-dmitry.torokhov@gmail.com


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