ASoC: amd: Fix a NULL vs IS_ERR() check in probe

The platform_device_register_full() function doesn't return NULL, it
returns error pointers.

Fixes: 7894a7e7 ("ASoC: amd: create ACP3x PCM platform device")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/amd/raven/pci-acp3x.c

@@ -97,10 +97,10 @@ static int snd_acp3x_probe(struct pci_dev *pci,
 		pdevinfo.size_data = sizeof(irqflags);
 
 		adata->pdev = platform_device_register_full(&pdevinfo);
-		if (!adata->pdev) {
+		if (IS_ERR(adata->pdev)) {
 			dev_err(&pci->dev, "cannot register %s device\n",
 				pdevinfo.name);
-			ret = -ENODEV;
+			ret = PTR_ERR(adata->pdev);
 			goto unmap_mmio;
 		}
 		break;