mac80211: ath10k: Allow to enable the thermal code of ath10k

mac80211: ath10k: Allow to enable the thermal code of ath10k

Some ath10k firmware versions allow to access the chip internal a
temperature sensor and allow to reduce the amount of the time when the card
is allowed to send. The latter is required on devices which tend to
overheat.

An userspace service has to read
/sys/class/ieee80211/phy*/device/hwmon/hwmon*/temp1_input regularly and
then decide how much the device has to be throttled. This can be done by
writing to /sys/class/ieee80211/phy*/device/cooling_device/cur_state. By
default it is not throttled (0) but it can be throttled up to 100(%).

Signed-off-by: Sven Eckelmann <sven.eckelmann@openmesh.com>
(backported from 4270847a2c2b8e4b890de16b51bd2e50c64077d2)
(rebased patches)
Signed-off-by: Jo-Philipp Wich <jo@mein.io>