ASoC: tpa6130a2: mark expected switch fall-through

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Addresses-Coverity-ID: 115164
Signed-off-by: NGustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

sound/soc/codecs/tpa6130a2.c

@@ -274,6 +274,7 @@ static int tpa6130a2_probe(struct i2c_client *client,
 	default:
 		dev_warn(dev, "Unknown TPA model (%d). Assuming 6130A2\n",
 			 data->id);
+		/* fall through */
 	case TPA6130A2:
 		regulator = "Vdd";
 		break;