ASoC: qcom: mark OF related data as maybe unused

The driver can be compile tested with !CONFIG_OF making certain data
unused:

  sound/soc/qcom/lpass-apq8016.c:294:34: warning: ‘apq8016_lpass_cpu_device_id’ defined but not used [-Wunused-const-variable=]
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201125164452.89239-10-krzk@kernel.orgSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/qcom/apq8016_sbc.c

@@ -167,7 +167,7 @@ static int apq8016_sbc_platform_probe(struct platform_device *pdev)
 	return devm_snd_soc_register_card(&pdev->dev, card);
 }
 
-static const struct of_device_id apq8016_sbc_device_id[]  = {
+static const struct of_device_id apq8016_sbc_device_id[] __maybe_unused = {
 	{ .compatible = "qcom,apq8016-sbc-sndcard" },
 	{},
 };

sound/soc/qcom/lpass-apq8016.c

@@ -291,7 +291,7 @@ static struct lpass_variant apq8016_data = {
 	.free_dma_channel	= apq8016_lpass_free_dma_channel,
 };
 
-static const struct of_device_id apq8016_lpass_cpu_device_id[] = {
+static const struct of_device_id apq8016_lpass_cpu_device_id[] __maybe_unused = {
 	{ .compatible = "qcom,lpass-cpu-apq8016", .data = &apq8016_data },
 	{}
 };

sound/soc/qcom/lpass-ipq806x.c

@@ -161,7 +161,7 @@ static struct lpass_variant ipq806x_data = {
 	.free_dma_channel	= ipq806x_lpass_free_dma_channel,
 };
 
-static const struct of_device_id ipq806x_lpass_cpu_device_id[] = {
+static const struct of_device_id ipq806x_lpass_cpu_device_id[] __maybe_unused = {
 	{ .compatible = "qcom,lpass-cpu", .data = &ipq806x_data },
 	{}
 };

sound/soc/qcom/lpass-sc7180.c

@@ -285,7 +285,7 @@ static struct lpass_variant sc7180_data = {
 	.free_dma_channel	= sc7180_lpass_free_dma_channel,
 };
 
-static const struct of_device_id sc7180_lpass_cpu_device_id[] = {
+static const struct of_device_id sc7180_lpass_cpu_device_id[] __maybe_unused = {
 	{.compatible = "qcom,sc7180-lpass-cpu", .data = &sc7180_data},
 	{}
 };