ixgbe: add hwmon interface to export thermal data

Some of our adapters have thermal data available, this patch exports
this data via hwmon sysfs interface.

Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Tested-by: Stephen Ko <stephen.s.ko@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c
index 97a9914..f90ec07 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c
@@ -849,6 +849,8 @@
 	.release_swfw_sync      = &ixgbe_release_swfw_sync_X540,
 	.disable_rx_buff	= &ixgbe_disable_rx_buff_generic,
 	.enable_rx_buff		= &ixgbe_enable_rx_buff_generic,
+	.get_thermal_sensor_data = NULL,
+	.init_thermal_sensor_thresh = NULL,
 };
 
 static struct ixgbe_eeprom_operations eeprom_ops_X540 = {