net: dsa: ocelot: accept 1000base-X for VSC9959 and VSC9953

Switches using the Lynx PCS driver support 1000base-X optical SFP
modules. Accept this interface type on a port.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20220510164320.10313-1-vladimir.oltean@nxp.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>