scripts: New script to update a device connected via adb

This new script allows to execute the update flow on an Android device
connected via adb to the host. At the moment, it supports both providing
the payload over the network with an "adb reverse" connection and to
push the payload to a file on the device.

Bug: 35903885
Test: system/update_engine/scripts/update_device.py ota.zip
Change-Id: I1c6d4df97ce85b6e30367a53b351353a954efbdc