fs/AllocatedPath: make the nullptr_t constructor public

src/db/plugins/simple/SimpleDatabasePlugin.cxx

@@ -79,7 +79,7 @@ inline SimpleDatabase::SimpleDatabase(AllocatedPath &&_path,
 #ifdef ENABLE_ZLIB
 	 compress(_compress),
 #endif
-	 cache_path(AllocatedPath::Null()),
+	 cache_path(nullptr),
 	 prefixed_light_song(nullptr) {
 }
 

src/db/update/InotifyUpdate.cxx

@@ -135,7 +135,7 @@ AllocatedPath
 WatchDirectory::GetUriFS() const noexcept
 {
 	if (parent == nullptr)
-		return AllocatedPath::Null();
+		return nullptr;
 
 	const auto uri = parent->GetUriFS();
 	if (uri.IsNull())