thermal: core: Relocate critical and hot trip handling

Modify handle_thermal_trip() to call handle_critical_trips() only after
finding that the trip temperature has been crossed on the way up and
remove the redundant temperature check from the latter.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>