platform/chrome: cros_ec_typec: Correct the Thunderbolt rounded/non-rounded cable support

Thunderbolt rounded/non-rounded cable support is two bits value. Correcting
it as per the Thunderbolt 3 cable discover mode VDO changes done in the
Thunderbolt 3 alternate mode header.

Signed-off-by: Utkarsh Patel <utkarsh.h.patel@intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
--
Changes in v2:
- Removed the fixes tag as there is no functional implication.
--
Link: https://lore.kernel.org/r/20201113202503.6559-3-utkarsh.h.patel@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>