input: convert sun4i-ts to use devm_thermal_zone_of_sensor_register

This changes the driver to use the devm_ version
of thermal_zone_of_sensor_register and cleans
up the  local points and unregister calls.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Lukasz Majewski <l.majewski@samsung.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Jens Thiele <karme@karme.de>
Cc: linux-input@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>