ALSA: ac97: Replace sprintf() with sysfs_emit()

For sysfs outputs, it's safer to use a new helper, sysfs_emit(),
instead of the raw sprintf() & co.  This patch replaces the open code
straightforwardly with a new helper.

Link: https://lore.kernel.org/r/20220801165639.26030-2-tiwai@suse.deSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/ac97/bus.c

@@ -460,7 +460,7 @@ static ssize_t vendor_id_show(struct device *dev,
 {
 	struct ac97_codec_device *codec = to_ac97_device(dev);
 
-	return sprintf(buf, "%08x", codec->vendor_id);
+	return sysfs_emit(buf, "%08x", codec->vendor_id);
 }
 DEVICE_ATTR_RO(vendor_id);