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 --cc drivers/net/ethernet/intel/Kconfig
Simple merge

diff --cc drivers/net/ethernet/intel/ixgbe/Makefile
Simple merge

diff --cc drivers/net/ethernet/intel/ixgbe/ixgbe.h
Simple merge

diff --cc drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c
Simple merge

diff --cc drivers/net/ethernet/intel/ixgbe/ixgbe_82599.c
Simple merge

diff --cc drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
Simple merge

diff --cc drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
Simple merge

diff --cc drivers/net/ethernet/intel/ixgbe/ixgbe_sysfs.c
Simple merge

diff --cc drivers/net/ethernet/intel/ixgbe/ixgbe_x540.c
Simple merge