side-switch: adapt do chassis state instance change

phosphor-state-manager moved to a multi chassis and multi host design
point. This made their corresponding service files instance based. For
backwards support, instance 0 will always represent the entire system,
so utilize that as the dependency in this service file.

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: I6a32ff5944b803cdeaa4ba9fd5faa0e3d49263fe
diff --git a/side-switch/phosphor-bmc-side-switch.service b/side-switch/phosphor-bmc-side-switch.service
index 0d03f34..f8c1357 100644
--- a/side-switch/phosphor-bmc-side-switch.service
+++ b/side-switch/phosphor-bmc-side-switch.service
@@ -6,8 +6,8 @@
 After=xyz.openbmc_project.Software.BMC.Updater.service
 Wants=xyz.openbmc_project.State.BMC.service
 After=xyz.openbmc_project.State.BMC.service
-Wants=xyz.openbmc_project.State.Chassis.service
-After=xyz.openbmc_project.State.Chassis.service
+Wants=xyz.openbmc_project.State.Chassis@0.service
+After=xyz.openbmc_project.State.Chassis@0.service
 Wants=xyz.openbmc_project.Settings.service
 After=xyz.openbmc_project.Settings.service
 ConditionPathExists=!/run/openbmc/host@0-on