Handle HWID and firmware updater for initramfs network boot

For initramfs network boot, the environment is minimal. Thus, we are
going to chroot into the installed environment and run firmware updater
and HWID updater there. This not only provides a full environment for
the updaters, but also makes them independent of initramfs environment.

BUG=chrome-os-partner:17368
TEST=Network boot and install with HWID bundle and firmware updater.

Change-Id: I235f8852737262157bdb7ce08611f65cad96c135
Signed-off-by: Vic Yang <victoryang@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/42090
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
2 files changed