Loaders: Depriorize disc streaming queue items.

We want the local items, if any, to load first.  This gives us icons, etc.

Core/FileLoaders/CachingFileLoader.cpp

@@ -289,6 +289,10 @@ void CachingFileLoader::StartReadAhead(s64 pos) {
 	th.detach();
 }
 
+bool CachingFileLoader::IsRemote() {
+	return backend_->IsRemote();
+}
+
 void CachingFileLoader::Cancel() {
 	backend_->Cancel();
 }