MDEV-24873 : galera.galera_as_slave_ctas MTR failed: Assertion `(&(&LOCK_thd_data)->m_mutex)->count > 0 && pthread_equal(pthread_self(), (&(&LOCK_thd_data)->m_mutex)->thread)' failed in sql_class.cc on THD::awake(killed_state)

Problem was that thd::awake assumes now that you hold THD::LOCK_thd_data
so we need to keep it when we call wsrep_thd_awake from
wsrep_abort_transaction.