side-switch: power off chassis in prep for update

When switching to a new level of firmware, ensure the host is off and
the chassis power is off before switching to the new firmware.

Tested:
- Verify power off works
<6> Checking for side switch reboot
<6> Running firmware version path is /xyz/openbmc_project/software/74575136
<6> Running firmware version priority is 1
<6> Running image is at priority 1, execute side switch
<see power off occur in journal>
<6> chassis power is off

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: Ifdb3e0c51fe66e55ebb1c3fca7097af49607bf35
2 files changed