Clarify that the SDL_GetStringRule means that SDL will automatically free the memory later.

include/SDL3/SDL_sensor.h

@@ -160,7 +160,7 @@ extern SDL_DECLSPEC SDL_SensorID *SDLCALL SDL_GetSensors(int *count);
  *
  * This can be called before any sensors are opened.
  *
- * The returned string follows the SDL_GetStringRule.
+ * The returned string follows the SDL_GetStringRule, and will be automatically freed later.
  *
  * \param instance_id the sensor instance ID.
  * \returns the sensor name, or NULL if `instance_id` is not valid.
@@ -229,7 +229,7 @@ extern SDL_DECLSPEC SDL_PropertiesID SDLCALL SDL_GetSensorProperties(SDL_Sensor
 /**
  * Get the implementation dependent name of a sensor.
  *
- * The returned string follows the SDL_GetStringRule.
+ * The returned string follows the SDL_GetStringRule, and will be automatically freed later.
  *
  * \param sensor the SDL_Sensor object.
  * \returns the sensor name, or NULL if `sensor` is NULL.