Allow a client to reconnect and continue authentication.

That allows clients like CISCO anyconnect to resume authentication
in a different session by keeping the username in a cookie. That
works only when a single password is used.

src/worker.h

@@ -76,6 +76,7 @@ struct http_req_st {
 	unsigned int next_header;
 	unsigned char cookie[COOKIE_SIZE];
 	unsigned int cookie_set;
+	unsigned int ocuser_cookie_set;
 	unsigned char master_secret[TLS_MASTER_SIZE];
 	unsigned int master_secret_set;