Extract process_incoming_push_reply from process_incoming_push_msg

Extract process_incoming_push_reply from process_incoming_push_msg

This is a small refactoring to make both function more readable. It also
eliminates the ret variable in process_incoming_push_msg that now serves
no purpose anymore.

Signed-off-by: Arne Schwabe <arne@rfc2549.org>
Acked-by: Antonio Quartulli <antonio@openvpn.net>
Message-Id: <20200709101603.11941-3-arne@rfc2549.org>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg20254.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>