Input: gpio-keys - fix check for disabling unsupported keys

Commit 4ea14a53 ("Input: gpio-keys - report
error when disabling unsupported key") tried let user know that they
attempted to disable an unsupported key, unfortunately the check is wrong
as it believes that all codes are invalid. Fix it by ensuring that keys
that we try to disable are subset of keys (or switches) that device
reports.

Fixes: 4ea14a53 ("Input: gpio-keys - report error when disabling unsupported key")
Reported-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Tested-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>