i40e: fix the restart auto-negotiation after FEC modified

When FEC mode was changed the link didn't know it because
the link was not reset and new parameters were not negotiated.
Set a flag 'I40E_AQ_PHY_ENABLE_ATOMIC_LINK' in 'abilities'
to restart the link and make it run with the new settings.

Fixes: 1d963401 ("i40e: Add support FEC configuration for Fortville 25G")
Signed-off-by: Jaroslaw Gawin <jaroslawx.gawin@intel.com>
Signed-off-by: Mateusz Palczewski <mateusz.palczewski@intel.com>
Tested-by: Dave Switzer <david.switzer@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/i40e/i40e_ethtool.c

@@ -1409,7 +1409,8 @@ static int i40e_set_fec_cfg(struct net_device *netdev, u8 fec_cfg)
 
 		memset(&config, 0, sizeof(config));
 		config.phy_type = abilities.phy_type;
-		config.abilities = abilities.abilities;
+		config.abilities = abilities.abilities |
+				   I40E_AQ_PHY_ENABLE_ATOMIC_LINK;
 		config.phy_type_ext = abilities.phy_type_ext;
 		config.link_speed = abilities.link_speed;
 		config.eee_capability = abilities.eee_capability;