Add endpoint/ticket_flag field for session

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index 4a0d6d9..c0c8c1e 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -588,6 +588,7 @@
 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
     /* Store minor version for later use with ticket serialization. */
     ssl->session_negotiate->tls_version = MBEDTLS_SSL_VERSION_TLS1_3;
+    ssl->session_negotiate->endpoint = ssl->conf->endpoint;
 #endif
 
     /* ...