Add guards for mbedtls_psa_crypto_free()

Signed-off-by: Przemek Stekiel <[email protected]>

programs/ssl/ssl_mail_client.c

@@ -805,7 +805,9 @@ exit:
     mbedtls_ssl_config_free(&conf);
     mbedtls_ctr_drbg_free(&ctr_drbg);
     mbedtls_entropy_free(&entropy);
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
     mbedtls_psa_crypto_free();
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
 
     mbedtls_exit(exit_code);
 }