io/i2c: fix the broken test
io/i2c: fix the broken test

Change-Id: Ie5ef9e256919ed0892fabe743d4542a2b1edc1b2
Reviewed-on: https://go-review.googlesource.com/24507
Reviewed-by: Jaana Burcu Dogan <347c19a639ce752a783b4ea325d6539ab4b4a262@google.com>

golang/exp,golang/exp,golang/exp