thermal: tegra: Use thermal_zone_for_each_trip() for walking trip points

It is generally inefficient to iterate over trip indices and call
thermal_zone_get_trip() every time to get the struct thermal_trip
corresponding to the given trip index, so modify the Tegra thermal
drivers to use thermal_zone_for_each_trip() for walking trips.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://patch.msgid.link/1819430.VLH7GnMWUR@rjwysocki.net


[ rjw: Dropped an unused local variable ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>