ASoC: dapm: Use IS_ERR_OR_NULL() helper function

Use the IS_ERR_OR_NULL() helper instead of open-coding a
NULL and an error pointer checks to simplify the code and
improve readability.

Signed-off-by: Hongbo Li <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/soc-dapm.c

···
 void snd_soc_dapm_debugfs_init(struct snd_soc_dapm_context *dapm,
 	struct dentry *parent)
 {
-	if (!parent || IS_ERR(parent))
+	if (IS_ERR_OR_NULL(parent))
 		return;
 
 	dapm->debugfs_dapm = debugfs_create_dir("dapm", parent);