ssl_client/server2 shouln't depend on timing.c

Would break test-ref-configs.pl.
diff --git a/programs/ssl/ssl_client2.c b/programs/ssl/ssl_client2.c
index 3ed0d29..89ef2c2 100644
--- a/programs/ssl/ssl_client2.c
+++ b/programs/ssl/ssl_client2.c
@@ -38,14 +38,12 @@
 
 #if !defined(MBEDTLS_ENTROPY_C) || \
     !defined(MBEDTLS_SSL_TLS_C) || !defined(MBEDTLS_SSL_CLI_C) || \
-    !defined(MBEDTLS_NET_C) || !defined(MBEDTLS_CTR_DRBG_C) || \
-    !defined(MBEDTLS_TIMING_C)
+    !defined(MBEDTLS_NET_C) || !defined(MBEDTLS_CTR_DRBG_C)
 int main( void )
 {
     mbedtls_printf("MBEDTLS_ENTROPY_C and/or "
            "MBEDTLS_SSL_TLS_C and/or MBEDTLS_SSL_CLI_C and/or "
-           "MBEDTLS_NET_C and/or MBEDTLS_CTR_DRBG_C and/or "
-           "MBEDTLS_TIMING_C not defined.\n");
+           "MBEDTLS_NET_C and/or MBEDTLS_CTR_DRBG_C and/or not defined.\n");
     return( 0 );
 }
 #else
@@ -392,7 +390,9 @@
     mbedtls_ssl_context ssl;
     mbedtls_ssl_config conf;
     mbedtls_ssl_session saved_session;
+#if defined(MBEDTLS_TIMING_C)
     mbedtls_timing_delay_context timer;
+#endif
 #if defined(MBEDTLS_X509_CRT_PARSE_C)
     uint32_t flags;
     mbedtls_x509_crt cacert;
@@ -1188,8 +1188,10 @@
 #endif
                 );
 
+#if defined(MBEDTLS_TIMING_C)
     mbedtls_ssl_set_timer_cb( &ssl, &timer, mbedtls_timing_set_delay,
                                             mbedtls_timing_get_delay );
+#endif
 
     mbedtls_printf( " ok\n" );
 
@@ -1488,8 +1490,10 @@
 
         mbedtls_net_close( server_fd );
 
+#if defined(MBEDTLS_TIMING_C)
         if( opt.reco_delay > 0 )
             mbedtls_timing_m_sleep( 1000 * opt.reco_delay );
+#endif
 
         mbedtls_printf( "  . Reconnecting with saved session..." );
         fflush( stdout );
@@ -1580,4 +1584,4 @@
 }
 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_ENTROPY_C && MBEDTLS_SSL_TLS_C &&
           MBEDTLS_SSL_CLI_C && MBEDTLS_NET_C && MBEDTLS_RSA_C &&
-          MBEDTLS_CTR_DRBG_C && MBEDTLS_TIMING_C */
+          MBEDTLS_CTR_DRBG_C MBEDTLS_TIMING_C */