boot_control_copy: A boot_control HAL implementation that works by copying.

This boot_control HAL implementation emulates A/B by copying the
contents of the boot partition of the requested slot to the boot
partition. It hence works with bootloaders that are not yet aware of
A/B. This code is only intended to be used for development.

Change-Id: Ifcc1ff19530f9e6db1de882807a25c785e1959de
4 files changed