qtest: unbreak non-TCG builds in bios-tables-test

the tests assume TCG is available, thus breaking
for TCG-only tests, where only the TCG accelerator option
is passed to the QEMU binary.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Message-Id: <20201013192123.22632-3-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

tests/qtest/bios-tables-test.c

@@ -127,6 +127,9 @@ static void free_test_data(test_data *data)
 {
     int i;
 
+    if (!data->tables) {
+        return;
+    }
     for (i = 0; i < data->tables->len; ++i) {
         cleanup_table_descriptor(&g_array_index(data->tables, AcpiSdtTable, i));
     }
@@ -656,6 +659,13 @@ static void test_acpi_one(const char *params, test_data *data)
     char *args;
     bool use_uefi = data->uefi_fl1 && data->uefi_fl2;
 
+#ifndef CONFIG_TCG
+    if (data->tcg_only) {
+        g_test_skip("TCG disabled, skipping ACPI tcg_only test");
+        return;
+    }
+#endif /* CONFIG_TCG */
+
     if (use_uefi) {
         /*
          * TODO: convert '-drive if=pflash' to new syntax (see e33763be7cd3)