Move erase handshake secrets

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/library/ssl_tls13_generic.c b/library/ssl_tls13_generic.c
index d15296f..4543d74 100644
--- a/library/ssl_tls13_generic.c
+++ b/library/ssl_tls13_generic.c
@@ -1060,11 +1060,7 @@
                     sizeof( ssl->handshake->state_local.finished_out.digest ),
                     &ssl->handshake->state_local.finished_out.digest_len,
                     ssl->conf->endpoint );
-    if( ssl->conf->endpoint == MBEDTLS_SSL_IS_CLIENT )
-    {
-        mbedtls_platform_zeroize( &ssl->handshake->tls13_hs_secrets,
-                                  sizeof( ssl->handshake->tls13_hs_secrets ) );
-    }
+
     if( ret != 0 )
     {
         MBEDTLS_SSL_DEBUG_RET( 1, "calculate_verify_data failed", ret );