stream: fix finished typo

#31509 introduced a slight typo.
Fortunately this typo does not have big impact due to
`isWritableFinished()`.

Fixes: #31509 (comment)

PR-URL: #31881
Fixes: #31509
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

Author: ronag

lib/internal/streams/end-of-stream.js

@@ -62,7 +62,7 @@ function eos(stream, opts, callback) {
   };
 
   let writableFinished = stream.writableFinished ||
-    (rState && rState.finished);
+    (wState && wState.finished);
   const onfinish = () => {
     writable = false;
     writableFinished = true;

test/parallel/test-stream-finished.js

@@ -312,7 +312,6 @@ testClosed((opts) => new Writable({ write() {}, ...opts }));
   }));
 }
 
-
 {
   const r = new Readable({
     autoDestroy: false
@@ -332,3 +331,14 @@ testClosed((opts) => new Writable({ write() {}, ...opts }));
     finished(rs, common.mustCall());
   }));
 }
+
+{
+  const d = new EE();
+  d._writableState = {};
+  d._writableState.finished = true;
+  finished(d, { readable: false, writable: true }, common.mustCall((err) => {
+    assert.strictEqual(err, undefined);
+  }));
+  d._writableState.errored = true;
+  d.emit('close');
+}