fix some format issues

Signed-off-by: Xiaofei Bai <xiaofei.bai@arm.com>
diff --git a/library/ssl_tls13_client.c b/library/ssl_tls13_client.c
index f1a31ca..0fb09c4 100644
--- a/library/ssl_tls13_client.c
+++ b/library/ssl_tls13_client.c
@@ -1572,7 +1572,7 @@
     int ret;
 
     ret = mbedtls_ssl_tls13_process_certificate( ssl );
-    if( ret != 0)
+    if( ret != 0 )
         return( ret );
 
     mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_CERTIFICATE_VERIFY );