ixgbe add thermal sensor support for x540 hardware

Add code to enable thermal sensors for the x540 hardware, as well as a
thermal interrupt check which will exit with a critical message of a
thermal overheat is detected. Intent of code allows other mac types to
be added with different configuration in the future.

Fixed in this version is the addition of setting the temp_sensor
capable flag which was previously only set for a specific mac.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>