handle_established_connection(): Don't mess with csp->ssl_with_(server|client)_is_opened

handle_established_connection(): Don't mess with csp->ssl_with_(server|client)_is_opened

This was a mismerge in 2111876638. The original code did
it in chat() were it doesn't hurt. Actually we don't need
to do it at all, as the variables are initialized to 0.

Zeroing the variables in handle_established_connection()
caused memory leaks as close_server_ssl_connection() and
close_client_ssl_connection() returned early,

Sponsored by: Robert Klemme