ASoc: wm8900: Drop empty spi_driver remove callback

A driver with a remove callback that just returns 0 behaves identically
to a driver with no remove callback at all. So simplify accordingly.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20211020125726.22946-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/wm8900.c

@@ -1252,17 +1252,11 @@ static int wm8900_spi_probe(struct spi_device *spi)
 	return ret;
 }
 
-static int wm8900_spi_remove(struct spi_device *spi)
-{
-	return 0;
-}
-
 static struct spi_driver wm8900_spi_driver = {
 	.driver = {
 		.name	= "wm8900",
 	},
 	.probe		= wm8900_spi_probe,
-	.remove		= wm8900_spi_remove,
 };
 #endif /* CONFIG_SPI_MASTER */