faft: Added USB PD power role swap test

Created new FAFT USB PD power role swap test script.

BRANCH=none
BUG=chrome-os-partner:49918
TEST=Manual
Tested using Samus and Plankton with workstation. Put Samus
in both source and sink starting roles. Verified that the
power swaps were validated. Verified the path where dualrole mode
is not supported.

Change-Id: Ifc29351e477b2b88922f9d31e0d5abd7ab1303d9
Signed-off-by: Scott Collyer <scollyer@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/324575
Reviewed-by: Wai-Hong Tam <waihong@chromium.org>
Reviewed-by: Todd Broch <tbroch@chromium.org>
3 files changed