fix unused variable issue

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 a9ef6b4..2e7f1d8 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -390,7 +390,7 @@
             }
 
             if( mbedtls_ssl_tls13_check_sig_alg_cert_key_match(
-                    ssl, *sig_alg, &key_cert->cert->pk ) )
+                                            *sig_alg, &key_cert->cert->pk ) )
             {
                 ssl->handshake->key_cert = key_cert;
                 MBEDTLS_SSL_DEBUG_CRT(