thermal/drivers/tegra: Use generic thermal_zone_get_trip() function

Replace a single call to thermal_zone_get_trip() to get a trip point
instead of calling the different ops->get_trip*

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20221003092602.1323944-11-daniel.lezcano@linaro.org