mfd: Support additional parent IDs for wm831x

Some newer device revisions add a second parent ID. Support this in
the device validity checks done at startup.

Signed-off-by: Mark Brown <[e-mail]>
Cc: [e-mail]
Signed-off-by: Samuel Ortiz <[e-mail]>

drivers/mfd/wm831x-core.c

···
 		dev_err(wm831x->dev, "Failed to read parent ID: %d\n", ret);
 		goto err;
 	}
-	if (ret != 0x6204) {
+	switch (ret) {
+	case 0x6204:
+	case 0x6246:
+		break;
+	default:
 		dev_err(wm831x->dev, "Device is not a WM831x: ID %x\n", ret);
 		ret = -EINVAL;
 		goto err;