HID: ACRUX - handle gamepads with different report layout

There are gamepads that share the same VID and PID but have different
report structure - instead of having 4 fields with one value they have
one field that can hold all 4 values. Make the driver cope with devices
using both styles.

Signed-off-by: Sergei Kolzun <x0r@dv-life.ru>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>