This commit contains fixes for error codes, which are needed
because OpenSSL 3.x and recent versions of GnuTLS have changed
the indication of error codes when the peer does not send
close_notify before closing the connection.
Problem was that controlling connection i.e. connection that
executed the query SET GLOBAL wsrep_reject_queries = ALL_KILL;
was also killed but server would try to send result from that
query to controlling connection resulting a assertion
mysqld: /home/jan/mysql/10.2-sst/include/mysql/psi/mysql_socket.h:738: inline_mysql_socket_send: Assertion `mysql_socket.fd != -1' failed.
as socket was closed when controlling connection was closed.
wsrep_close_client_connections()
Do not close controlling connection and instead of
wsrep_close_thread() we do now soft kill by THD::awake
wsrep_reject_queries_update()
Call wsrep_close_client_connections using current thd.
