Revert "Use guaranteed random number generator." Fixes #4400

This reverts commit 9f6899ac82.

src/playlist/playlist.cpp

@@ -1914,11 +1914,8 @@ void Playlist::ReshuffleIndices() {
 
       // Shuffle them
       QStringList shuffled_album_keys = album_key_set.toList();
-      std::random_shuffle(
-          shuffled_album_keys.begin(),
-          shuffled_album_keys.end(),
-          // http://xkcd.com/221/
-          [](int x) { return 4; });
+      std::random_shuffle(shuffled_album_keys.begin(),
+                          shuffled_album_keys.end());
 
       // If the user is currently playing a song, force its album to be first.
       if (current_virtual_index_ != -1) {