Rename state_change to continue_tls_process

Rename state_change to continue_tls_process

The name state_change is more confusing than helpful as it not really
indicates if there was a state change but rather if processing should
be continued. There even some states that are definitively state changes
(setting to_link buffer) that require continue_tls_process to be set
to false.

Change-Id: Ib6d713f2eb08a4c39d97de3e1a4a832cedc09585
Acked-by: Frank Lichtenheld <frank@lichtenheld.com>
Signed-off-by: Arne Schwabe <arne@rfc2549.org>
Message-Id: <20231128103704.61046-1-frank@lichtenheld.com>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg27571.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>