control: Restore `Current` property for each zone

Each JSON based zone object restores the persisted state of their
`Current` property when constructed. If no `Current` property value is
found for the zone, the default of the Control.ThermalMode interface is
used.

After the restore is done on each zone object, the `emit_object_added` for
that zone object can be done.

Change-Id: Id59eb511d76fb45a318660ffd9c0b6a776ba7770
Signed-off-by: Matthew Barth <msbarth@us.ibm.com>
2 files changed