net: pcs: pcs-lynx: implement pcs_inband_caps() method

Report the PCS in-band capabilities to phylink for the Lynx PCS.

Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/E1tJ8NM-006L5J-AH@rmk-PC.armlinux.org.uk


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