ASoC: sam9g20_wm8731: Simplify some error message

dev_err_probe() already prints the error code in a human readable way, so
there is no need to duplicate it as a numerical value at the end of the
message.

Fixes: 29f4078f ("ASoC: sam9g20_wm8731: Use dev_err_probe() for snd_soc_register_card()")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/fb959b3bda689aa47e1fbe9948de957b77530b24.1659764734.git.christophe.jaillet@wanadoo.frSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/atmel/sam9g20_wm8731.c

@@ -172,7 +172,7 @@ static int at91sam9g20ek_audio_probe(struct platform_device *pdev)
 	ret = snd_soc_register_card(card);
 	if (ret) {
 		dev_err_probe(&pdev->dev, ret,
-			      "snd_soc_register_card() failed: %d\n", ret);
+			      "snd_soc_register_card() failed\n");
 		goto err;
 	}