ASoC: spear: fix error return code in spdif_in_probe()

platform_get_irq() returns an error code, but the spdif_in driver
ignores it and always returns -EINVAL. This is not correct, and
prevents -EPROBE_DEFER from being propagated properly.

Notice that platform_get_irq() no longer returns 0 on error:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e330b9a6bb35dc7097a4f02cb1ae7b6f96df92af

Print error message and propagate the return value of platform_get_irq
on failure.
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/spear/spdif_in.c

@@ -223,8 +223,10 @@ static int spdif_in_probe(struct platform_device *pdev)
 
 	host->io_base = io_base;
 	host->irq = platform_get_irq(pdev, 0);
-	if (host->irq < 0)
-		return -EINVAL;
+	if (host->irq < 0) {
+		dev_warn(&pdev->dev, "failed to get IRQ: %d\n", host->irq);
+		return host->irq;
+	}
 
 	host->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(host->clk))