add namespace on setProperty

The function was moved to a utility interface so need the namespace
added

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: Ia6fccbec909ad83bd5f1d6a335b1dc55948d2bfe
diff --git a/discover_system_state.cpp b/discover_system_state.cpp
index a529a0a..bfabdaf 100644
--- a/discover_system_state.cpp
+++ b/discover_system_state.cpp
@@ -144,8 +144,9 @@
                  RestorePolicy::convertPolicyFromString(powerPolicy))
         {
             info("power_policy=ALWAYS_POWER_OFF, set requested state to off");
-            setProperty(bus, hostPath, HOST_BUSNAME, "RequestedHostTransition",
-                        convertForMessage(server::Host::Transition::Off));
+            phosphor::state::manager::utils::setProperty(
+                bus, hostPath, HOST_BUSNAME, "RequestedHostTransition",
+                convertForMessage(server::Host::Transition::Off));
         }
         else if (RestorePolicy::Policy::Restore ==
                  RestorePolicy::convertPolicyFromString(powerPolicy))