examples: Do not usre deprecated functions

Signed-off-by: Andreas Schneider <asn@cryptomilk.org>

examples/knownhosts.c

@@ -40,7 +40,7 @@ int verify_knownhost(ssh_session session){
 
   state=ssh_is_server_known(session);
 
-  rc = ssh_get_publickey(session, &srv_pubkey);
+  rc = ssh_get_server_publickey(session, &srv_pubkey);
   if (rc < 0) {
       return -1;
   }