HID: wiimote: extend driver description

The hid-wiimote driver supports more than the Wii Remote. Nintendo
produced many devices based on the Wii Remote, which have extension
devices built-in. It is not clear to many users, that these devices have
anything in common with the Wii Remote, so fix the driver description.

This also updates the copyright information for the coming hotplugging
rework.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>