dm: sandbox: cros_ec: Move sandbox cros_ec to driver module

Adjust the sandbox cros_ec emulation driver to work with driver model, and
switch over to driver model for sandbox cros_ec.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2 files changed