Fix schannel TLS 1.3 reneg delay

With TLS 1.3 the client goes through renegotiation
when using Schannel. The status returned is OK and
we can immediately continue, so do that.

Change-Id: I831eaae318df9d94b5fb7672db7e407d94f9da56
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>

src/network/ssl/qsslsocket_schannel.cpp

@@ -1696,6 +1696,8 @@ void QSslSocketBackendPrivate::continueHandshake()
         if (!renegotiate()) {
             disconnectFromHost();
             return;
+        } else if (intermediateBuffer.size() || plainSocket->bytesAvailable()) {
+            continueHandshake();
         }
         break;
     }