[lk]: Add support for SSD implementation of image upgrade

Recovery sets bootloader messages in MISC partition as part of SSD
process.For NAND target, we set cookie in FOTA partition. For eMMC
target, recovery creates cookie file. We read the SSD update status
from the early boot chain and send it to recovery to finish up the
process.

Change-Id: I5d0d2dbe06bf1773fe9daaf6904f8e59a4c30ad4
9 files changed