Add guards for mbedtls_psa_crypto_free()

Signed-off-by: Przemek Stekiel <przemyslaw.stekiel@mobica.com>
diff --git a/programs/fuzz/fuzz_client.c b/programs/fuzz/fuzz_client.c
index 3776b8a..2de51a6 100644
--- a/programs/fuzz/fuzz_client.c
+++ b/programs/fuzz/fuzz_client.c
@@ -191,7 +191,9 @@
     mbedtls_ctr_drbg_free(&ctr_drbg);
     mbedtls_ssl_config_free(&conf);
     mbedtls_ssl_free(&ssl);
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
     mbedtls_psa_crypto_free();
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
 
 #else
     (void) Data;