ERR_remove_thread_state() frees the error queue associated with thread tid.
If tid == NULL, the current thread will have its error queue removed.
Since error queue data structures are allocated automatically for new
threads, they must be freed when threads are terminated in order to
avoid memory leaks.
ERR_remove_state is deprecated and has been replaced by
ERR_remove_thread_state. Since threads in OpenSSL are no longer identified
by unsigned long values any argument to this function is ignored. Calling
ERR_remove_state is equivalent to ERR_remove_thread_state(NULL).