HID: wiimote: Add register/eeprom memory support

The wiimote allows direct access to its memory mapped registers and
internal eeprom. This adds support to access this memory and handle
memory events.

There are two macros which wrap up the memory access functions to avoid
accidentally overwriting sensitive eeprom data because a boolean value
was wrongly set.

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