stream: remove dead code

Remove unreachable code. `state.ended` is always set to true
in this part of the code. The `else` clause can't be executed.

lib/_stream_readable.js

@@ -521,11 +521,7 @@ function onEofChunk(stream, state) {
     state.emittedReadable = true;
     // We have to emit readable now that we are EOF. Modules
     // in the ecosystem (e.g. dicer) rely on this event being sync.
-    if (state.ended) {
-      emitReadable_(stream);
-    } else {
-      process.nextTick(emitReadable_, stream);
-    }
+    emitReadable_(stream);
   }
 }