Revert "io: add support for activating TLS thread safety workaround"

This reverts commit edea818371.

The workaround for the GNUTLS bug was not correct and it was
decided to rely on GNUTLS being patched by distros instead,
or users manually disabling use of the problematic ciphers.

Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

include/io/channel.h

@@ -47,7 +47,6 @@ enum QIOChannelFeature {
     QIO_CHANNEL_FEATURE_WRITE_ZERO_COPY,
     QIO_CHANNEL_FEATURE_READ_MSG_PEEK,
     QIO_CHANNEL_FEATURE_SEEKABLE,
-    QIO_CHANNEL_FEATURE_CONCURRENT_IO,
 };
 
 

io/channel-tls.c

@@ -261,11 +261,6 @@ void qio_channel_tls_handshake(QIOChannelTLS *ioc,
 {
     QIOTask *task;
 
-    if (qio_channel_has_feature(QIO_CHANNEL(ioc),
-                                QIO_CHANNEL_FEATURE_CONCURRENT_IO)) {
-        qcrypto_tls_session_require_thread_safety(ioc->session);
-    }
-
     task = qio_task_new(OBJECT(ioc),
                         func, opaque, destroy);