ASoC: ti: davinci-mcasp: Use platform_get_irq_byname_optional

Depending on the integration of McASP either the 'common' or the
'rx' and 'tx' or only the 'tx' interrupt number is valid, provided.

By switching to platform_get_irq_byname_optional() we can clean up the
bootlog from messages like:

davinci-mcasp 2ba0000.mcasp: IRQ common not found

The irq number == 0 is not valid, fix the check at the same time.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20201106072551.689-2-peter.ujfalusi@ti.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/ti/davinci-mcasp.c

@@ -2202,8 +2202,8 @@ static int davinci_mcasp_probe(struct platform_device *pdev)
 
 	mcasp->dev = &pdev->dev;
 
-	irq = platform_get_irq_byname(pdev, "common");
-	if (irq >= 0) {
+	irq = platform_get_irq_byname_optional(pdev, "common");
+	if (irq > 0) {
 		irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%s_common",
 					  dev_name(&pdev->dev));
 		if (!irq_name) {
@@ -2223,8 +2223,8 @@ static int davinci_mcasp_probe(struct platform_device *pdev)
 		mcasp->irq_request[SNDRV_PCM_STREAM_CAPTURE] = ROVRN;
 	}
 
-	irq = platform_get_irq_byname(pdev, "rx");
-	if (irq >= 0) {
+	irq = platform_get_irq_byname_optional(pdev, "rx");
+	if (irq > 0) {
 		irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%s_rx",
 					  dev_name(&pdev->dev));
 		if (!irq_name) {
@@ -2242,8 +2242,8 @@ static int davinci_mcasp_probe(struct platform_device *pdev)
 		mcasp->irq_request[SNDRV_PCM_STREAM_CAPTURE] = ROVRN;
 	}
 
-	irq = platform_get_irq_byname(pdev, "tx");
-	if (irq >= 0) {
+	irq = platform_get_irq_byname_optional(pdev, "tx");
+	if (irq > 0) {
 		irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%s_tx",
 					  dev_name(&pdev->dev));
 		if (!irq_name) {