Pull file path into elog Entry constructor

The path property on the FilePath interfaces was previously being set
after the entry object was created, sending a properties changed signal
after the interfaces added signal.

Since the path can be known at the time the entry is constructed, pass
it into the constructor instead so no extra signal will be sent.

Change-Id: I1150236d23cecb1df78e3fb4ae641c75b488af37
diff --git a/log_manager.cpp b/log_manager.cpp
index 6513bd9..d12630a 100644
--- a/log_manager.cpp
+++ b/log_manager.cpp
@@ -234,13 +234,13 @@
     AssociationList objects{};
     processMetadata(errMsg, additionalData, objects);
 
-    auto e = std::make_unique<Entry>(busLog, objPath, entryId,
-                                     ms, // Milliseconds since 1970
-                                     errLvl, std::move(errMsg),
-                                     std::move(additionalData),
-                                     std::move(objects), fwVersion, *this);
-    auto path = serialize(*e);
-    e->path(path);
+    auto e = std::make_unique<Entry>(
+        busLog, objPath, entryId,
+        ms, // Milliseconds since 1970
+        errLvl, std::move(errMsg), std::move(additionalData),
+        std::move(objects), fwVersion, getEntrySerializePath(entryId), *this);
+
+    serialize(*e);
 
     if (isQuiesceOnErrorEnabled() && isCalloutPresent(*e))
     {