CRAS: tests - Fix iodev_list_unittest

Fallback devices' state should be initialized to closed in each
test cases.
The incorrect iodev state misled a few test cases, fixing them.

BUG=chromium:890242
TEST=Unittest

Change-Id: Ie3220e6d51432d9ec02b5fde0003d2e928e49074
Reviewed-on: https://chromium-review.googlesource.com/1257488
Commit-Ready: Hsinyu Chao <hychao@chromium.org>
Tested-by: Hsinyu Chao <hychao@chromium.org>
Reviewed-by: Dylan Reid <dgreid@chromium.org>
1 file changed