CEC: Switch ARC hardware circuit before device update

Audio Return Channel hardware circuit was being switched after
the device update initiated by hotplug event. The device instance
was already removed by the time ARC update was attempted, hence
caused an exception.

This CL ensure the config change is done in advance, when
the AVR device instance is still present.

Bug: 19250400
Change-Id: I31cf682f5c8d1a279a0703d10fe182f3da23d3db