net: phy: remove unused feature array declarations

After 12d5151b ("net: phy: remove leftovers from switch to linkmode
bitmaps") the following declarations are unused and can be removed too.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Reviewed-by: Mateusz Polchlopek <mateusz.polchlopek@intel.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/b2883c75-4108-48f2-ab73-e81647262bc2@gmail.com


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