platform/chrome: cros_ec_proto: Introduce cros_ec_get_cmd_versions()

platform/chrome: cros_ec_proto: Introduce cros_ec_get_cmd_versions()

Retrieving the supported versions of a command is a fairly common
operation. Provide a helper for it.

If the command is not supported at all the EC returns
-EINVAL/EC_RES_INVALID_PARAMS.

This error is translated into an empty version mask as that is easier to
handle for callers and they don't need to know about the error details.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20240630-cros_ec-charge-control-v5-3-8f649d018c52@weissschuh.net
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>