thermal: core: improve power actor documentation

Simple improvement on clarity and removal of checkpatch warning
in the documentation of power actor kernel doc.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

drivers/thermal/thermal_core.c

@@ -1206,12 +1206,13 @@ int power_actor_get_min_power(struct thermal_cooling_device *cdev,
 }
 
 /**
- * power_actor_set_power() - limit the maximum power that a cooling device can consume
+ * power_actor_set_power() - limit the maximum power a cooling device consumes
  * @cdev:	pointer to &thermal_cooling_device
  * @instance:	thermal instance to update
  * @power:	the power in milliwatts
  *
- * Set the cooling device to consume at most @power milliwatts.
+ * Set the cooling device to consume at most @power milliwatts. The limit is
+ * expected to be a cap at the maximum power consumption.
  *
  * Return: 0 on success, -EINVAL if the cooling device does not
  * implement the power actor API or -E* for other failures.