i40e: Change user notification of non-SFP module in i40e_get_module_info()

Make the driver not produce an error message on
"ethtool -m ethX" command when a non-SFP module is encountered
hence there is no possibility to read the EEPROM.
Make the message to appear in the debug log rather
than as an error string.

Change the return code to -EOPNOTSUPP and the string to make
it more verbose.

Signed-off-by: Andrii Staikov <andrii.staikov@intel.com>
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
CC: Stefan Assmann <sassmann@redhat.com>
CC: Michal Schmidt <mschmidt@redhat.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://lore.kernel.org/r/20231113231047.548659-4-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: CuriousPanCake

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

@@ -5584,8 +5584,8 @@ static int i40e_get_module_info(struct net_device *netdev,
 		modinfo->eeprom_len = I40E_MODULE_QSFP_MAX_LEN;
 		break;
 	default:
-		netdev_err(vsi->netdev, "Module type unrecognized\n");
-		return -EINVAL;
+		netdev_dbg(vsi->netdev, "SFP module type unrecognized or no SFP connector used.\n");
+		return -EOPNOTSUPP;
 	}
 	return 0;
 }