Doc: Fix broken link to QTextStream::OK

Change-Id: I10f7f17410be731b50c0d06ad05d387eaaec07d2
Reviewed-by: Alexei Cazacov <alexei.cazacov@qt.io>
Reviewed-by: Nicholas Bennett <nicholas.bennett@qt.io>

src/corelib/serialization/qtextstream.cpp

@@ -2562,7 +2562,7 @@ QTextStream &QTextStream::operator<<(const void *ptr)
     \fn QTextStream::operator bool() const
     \since 6.10
 
-    Returns whether this stream has no errors (status() == \l{OK}).
+    Returns whether this stream has no errors (status() returns \c{Status::OK}).
 */
 
 namespace Qt {