net: phy: stop exporting feature arrays which aren't used outside phylib

Stop exporting feature arrays which aren't used outside phylib.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Mateusz Polchlopek <mateusz.polchlopek@intel.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/01886672-4880-4ca8-b7b0-94d40f6e0ec5@gmail.com


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