Like the Apple Magic Keyboard 2015, when connected over USB, the 2021
version with fingerprint reader registers 2 different interfaces. One of
them is used to report the battery level.

However, unlike when connected over Bluetooth, the battery level is not
reported automatically and it is required to fetch it manually.

Add the APPLE_RDESC_BATTERY quirk to fix the battery report descriptor
and manually fetch the battery level.

Tested with the ANSI variant of the keyboard with and without numpad.
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>