HID: roccat: cleanup of kovaplus module

Partially removed unneeded informations and data caching.
Moved code nearer to format of newer drivers.
Added "info" sysfs attribute to support device reset and deprecate other attributes.

Signed-off-by: Stefan Achatz <erazor_de@users.sourceforge.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>