thermal/drivers/of-thermal: Move the of_thermal_free_zone() to the init section

The function of_thermal_free_zone() is only used the initialization
function which all belonging to the init section.

Move it also to the __init section.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20191219222154.16100-2-daniel.lezcano@linaro.org

drivers/thermal/of-thermal.c

@@ -977,7 +977,7 @@ free_tz:
 	return ERR_PTR(ret);
 }
 
-static inline void of_thermal_free_zone(struct __thermal_zone *tz)
+static __init void of_thermal_free_zone(struct __thermal_zone *tz)
 {
 	struct __thermal_bind_params *tbp;
 	int i, j;