treewide: Cleanup signal emission

Don't emit properties changed prior to interfaces added.

Change-Id: I7f88b8052a323ca49ce9f16fe446596213e3fdb5
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/src/system_configuration.cpp b/src/system_configuration.cpp
index 192f12d..0ba4d82 100644
--- a/src/system_configuration.cpp
+++ b/src/system_configuration.cpp
@@ -28,9 +28,9 @@
     Iface(bus, objPath.c_str(), Iface::action::defer_emit),
     bus(bus)
 {
-    SystemConfigIntf::hostName(getHostNameFromSystem());
+    SystemConfigIntf::hostName(getHostNameFromSystem(), true);
 
-    this->emit_object_added();
+    emit_object_added();
 }
 
 std::string SystemConfiguration::hostName(std::string name)