ice: Add space to unknown speed

Add space to the end of 'Unknown' string  in  order to avoid
concatenation with 'bps' string when formatting netdev log message.

Signed-off-by: Simon Perron Caissy <simon.perron.caissy@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/ice/ice_main.c

@@ -667,7 +667,7 @@ void ice_print_link_msg(struct ice_vsi *vsi, bool isup)
 		speed = "100 M";
 		break;
 	default:
-		speed = "Unknown";
+		speed = "Unknown ";
 		break;
 	}