thermal: cpu_cooling: document cpufreq_get_cooling_level

Add documentation for cpufreq_get_cooling_level. As this
is an exported function, it has to be documented.

Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Acked-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
1 file changed