Adapt prototypes of ticket handling functions

This is an intermediate step. The ssl_config argument will be replace by a
ticket context next.
diff --git a/include/mbedtls/ssl_ticket.h b/include/mbedtls/ssl_ticket.h
index 9143024..d4ef736 100644
--- a/include/mbedtls/ssl_ticket.h
+++ b/include/mbedtls/ssl_ticket.h
@@ -31,12 +31,17 @@
 #endif
 
 /* Temporary, WIP */
-int mbedtls_ssl_ticket_write( mbedtls_ssl_context *ssl, size_t *tlen );
+int mbedtls_ssl_ticket_write( const mbedtls_ssl_config *conf,
+                              const mbedtls_ssl_session *session,
+                              unsigned char *start,
+                              const unsigned char *end,
+                              size_t *tlen );
 
 /* Temporary, WIP */
-int mbedtls_ssl_ticket_parse( mbedtls_ssl_context *ssl,
-                             unsigned char *buf,
-                             size_t len );
+int mbedtls_ssl_ticket_parse( const mbedtls_ssl_config *conf,
+                              mbedtls_ssl_session *session,
+                              unsigned char *buf,
+                              size_t len );
 
 #ifdef __cplusplus
 }