iwlwifi: critical temperature enter/exit condition

If advance thermal throttling is used the driver need to pass both
"enter" and "exit" temperature to uCode.

Using different critical temperature threshold for legacy and advance
thermal throttling management based on the type of thermal throttling
method is used except 1000.
For 1000, it use advance thermal throttling critical temperature
threshold, but with legacy thermal management implementation until ucode
has the necessary implementations in place.

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>