openconnect: added upstream patch for dynamic IPs

That requires an update to ocserv as well to advertise them.
ocserv: enable the X-CSTP-DynDNS header

Signed-off-by: Nikos Mavrogiannopoulos <nmav@gnutls.org>
openconnect: simplified cmdline appending

Signed-off-by: Nikos Mavrogiannopoulos <nmav@gnutls.org>