platform/chrome: cros_ec_proto: add Kunit tests for cros_ec_query_all()

cros_ec_query_all() sends multiple host commands to EC for querying
supported protocols and settings.

Add required mock for interacting with cros_ec_query_all() and Kunit
tests.

Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://lore.kernel.org/r/20220609084957.3684698-3-tzungbi@kernel.org