ALSA: aloop: Use standard print API

Use pr_err() instead of open-coded printk() just for code
simplification.
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20240807133452.9424-13-tiwai@suse.de

sound/drivers/aloop.c

@@ -1896,7 +1896,7 @@ static int __init alsa_card_loopback_init(void)
 	}
 	if (!cards) {
 #ifdef MODULE
-		printk(KERN_ERR "aloop: No loopback enabled\n");
+		pr_err("aloop: No loopback enabled\n");
 #endif
 		loopback_unregister_all();
 		return -ENODEV;