discover-system-state: add multi-host support

Add HostObjects class to fetch paths of settings d-bus objects under
/xyz/openbmc_project/control/hostX .

Signed-off-by: Potin Lai <potin.lai@quantatw.com>
Change-Id: I1dc55ec389e94e6c85aa7031b304f8c4ed15dc71
diff --git a/service_files/phosphor-discover-system-state@.service b/service_files/phosphor-discover-system-state@.service
index 4fbb186..345266c 100644
--- a/service_files/phosphor-discover-system-state@.service
+++ b/service_files/phosphor-discover-system-state@.service
@@ -1,13 +1,13 @@
 [Unit]
 Description=Reboot If Enabled
-Wants=mapper-wait@-xyz-openbmc_project-control-host0-power_restore_policy.service
-After=mapper-wait@-xyz-openbmc_project-control-host0-power_restore_policy.service
+Wants=mapper-wait@-xyz-openbmc_project-control-host%i-power_restore_policy.service
+After=mapper-wait@-xyz-openbmc_project-control-host%i-power_restore_policy.service
 Wants=mapper-wait@-xyz-openbmc_project-state-host%i.service
 After=mapper-wait@-xyz-openbmc_project-state-host%i.service
 Wants=mapper-wait@-xyz-openbmc_project-state-chassis%i.service
 After=mapper-wait@-xyz-openbmc_project-state-chassis%i.service
-Wants=mapper-wait@-xyz-openbmc_project-state-bmc%i.service
-After=mapper-wait@-xyz-openbmc_project-state-bmc%i.service
+Wants=mapper-wait@-xyz-openbmc_project-state-bmc0.service
+After=mapper-wait@-xyz-openbmc_project-state-bmc0.service
 After=op-reset-chassis-on@%i.service
 ConditionPathExists=!/run/openbmc/chassis@%i-on