Fix substitutions being broken after freezing - actually store the original state in registry copies, not the computed state, which is wrong because it only sees the sub, not the original.

src/main/java/net/minecraftforge/fml/common/registry/FMLControlledNamespacedRegistry.java

@@ -195,6 +195,8 @@ public class FMLControlledNamespacedRegistry<I extends IForgeRegistryEntry<I>> e
         {
             activateSubstitution(resloc);
         }
+        this.substitutionOriginals.clear();
+        this.substitutionOriginals.putAll(otherRegistry.substitutionOriginals);
     }
 
     // public api