thunderbolt: Silently ignore CLx enabling in case CLx is not supported

We can't enable CLx if it is not supported either by the host or device,
or by the USB4/TBT link (e.g. when an optical cable is used).
We silently ignore CLx enabling in this case.

Signed-off-by: Gil Fine <gil.fine@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>