HID: hid-samsung: add support for Creative Desktop Wireless 6000

Add support for the multimedia buttons of the Creative Desktop Wireless 6000
keyboard/mouse combo which are not currently handled by the default/samsung HID
driver.

Signed-off-by: Don Prince <dhprince-devel@yahoo.co.uk>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>