chassis-state-manager: Clean up sdbusplus exception handling

In order to support error handling for message operations, we need to
make sure we are catching exceptions thrown by sdbusplus.

Tested:
    Built / ran on a fully tray pulled zaius. Correctly detected the
    host was off and did the automatic transition to boot the machine
    at BMC start. Chassis power commands still work as expected and
    show up as state transitions.

Change-Id: I3468209b215df6535bb5357a62335da151d81897
Signed-off-by: William A. Kennington III <wak@google.com>
1 file changed