faft: Add EC related client attribute

To determine if an EC test can run on a device, we need information
about EC on the device. Let's add this to FAFT client attribute.

BUG=chrome-os-partner:11629
TEST=none

Change-Id: Ide85e33243dcae1953a105665ba37721a143aec1
Reviewed-on: https://gerrit.chromium.org/gerrit/28055
Reviewed-by: Tom Wai-Hong Tam <waihong@chromium.org>
Commit-Ready: Vic Yang <victoryang@chromium.org>
Tested-by: Vic Yang <victoryang@chromium.org>
1 file changed