faft: Call servo to toggle recovery switch

Don't directly set the servo fields. Call the servo layer to toggle
recovery switch. And also remove the out-dated hold_cold_reset config.

BUG=chrome-os-partner:16231
TEST=Ran firmware_DevMode on Samus.

Change-Id: I88b945cdfc037c08b6615169806e53ed846fcdc9
Reviewed-on: https://chromium-review.googlesource.com/270765
Trybot-Ready: Tom Tam <waihong@google.com>
Tested-by: Tom Tam <waihong@google.com>
Reviewed-by: Yusuf Mohsinally <mohsinally@chromium.org>
Commit-Queue: Tom Tam <waihong@google.com>
3 files changed