ASoC: rt5640: Omit ACPI match table only if !ACPI

The ACPI_PTR() macro evaluates to NULL if ACPI is disabled and hence the
ACPI match table won't be used, causing the compiler to complain. Avoid
this by protecting the table using an #ifdef CONFIG_ACPI.
Signed-off-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NMark Brown <broonie@linaro.org>

sound/soc/codecs/rt5640.c

@@ -2082,11 +2082,13 @@ static const struct i2c_device_id rt5640_i2c_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, rt5640_i2c_id);
 
+#ifdef CONFIG_ACPI
 static struct acpi_device_id rt5640_acpi_match[] = {
 	{ "INT33CA", 0 },
 	{ },
 };
 MODULE_DEVICE_TABLE(acpi, rt5640_acpi_match);
+#endif
 
 static int rt5640_parse_dt(struct rt5640_priv *rt5640, struct device_node *np)
 {