thermal: trip_point_temp_store() calls thermal_zone_device_update()

trip_point_temp_store() updates trip temperature. It should call
thermal_zone_device_update() immediately.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>