i2c: cros-ec-tunnel: Fix ACPI identifier

The initial patch was using the incorrect identifier.

Fixes: 9af1563a ("i2c: cros-ec-tunnel: Make the device acpi compatible")
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>