chassis-state-manager: Add multi-chassis support

Add multi-chassis management support, each chassis bus separates by
giving a unique chassis id.

Current code only support single chassis, and alway assume bus name is
"xyz.openbmc_project.State.Chassis".

This patch allow user to launch chassis-state-manager with a chassis id,
and chassis id is added into service bus name for identification.

Because there are many places hardcode with bus name
"xyz.openbmc_project.State.Chassis", if chassis id is 0,
chassis-state-manager will request both
"xyz.openbmc_project.State.Chassis" and
"xyz.openbmc_project.State.Chassis0" bus name to meet backwards
compatibility.

Tested on Bletchley:
root@bletchley:~# busctl tree xyz.openbmc_project.State.Chassis
`-/xyz
  `-/xyz/openbmc_project
    `-/xyz/openbmc_project/state
      `-/xyz/openbmc_project/state/chassis0
root@bletchley:~# busctl tree xyz.openbmc_project.State.Chassis0
`-/xyz
  `-/xyz/openbmc_project
    `-/xyz/openbmc_project/state
      `-/xyz/openbmc_project/state/chassis0
root@bletchley:~# busctl tree xyz.openbmc_project.State.Chassis1
`-/xyz
  `-/xyz/openbmc_project
    `-/xyz/openbmc_project/state
      `-/xyz/openbmc_project/state/chassis1
......

patch dependencies:
https://gerrit.openbmc-project.xyz/c/openbmc/phosphor-state-manager/+/51465

Signed-off-by: Potin Lai <potin.lai@quantatw.com>
Change-Id: I2ce3e9ab2c95a2688143f4e3775da164a5c33c19
diff --git a/service_files/meson.build b/service_files/meson.build
index 2df30e6..87659ca 100644
--- a/service_files/meson.build
+++ b/service_files/meson.build
@@ -7,7 +7,7 @@
     'phosphor-reset-host-running@.service',
     'phosphor-reset-sensor-states@.service',
     'xyz.openbmc_project.State.BMC.service',
-    'xyz.openbmc_project.State.Chassis.service',
+    'xyz.openbmc_project.State.Chassis@.service',
     'xyz.openbmc_project.State.Host@.service',
     'xyz.openbmc_project.State.Hypervisor.service',
     'xyz.openbmc_project.State.ScheduledHostTransition.service',