ASoC: cs43130: fix a NULL pointer dereference

In case create_singlethread_workqueue fails, the fix returns
-ENOMEM to avoid potential NULL pointer dereference.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/codecs/cs43130.c b/sound/soc/codecs/cs43130.c
index 3f7b255..80d6727 100644
--- a/sound/soc/codecs/cs43130.c
+++ b/sound/soc/codecs/cs43130.c
@@ -2322,6 +2322,8 @@
 			return ret;
 
 		cs43130->wq = create_singlethread_workqueue("cs43130_hp");
+		if (!cs43130->wq)
+			return -ENOMEM;
 		INIT_WORK(&cs43130->work, cs43130_imp_meas);
 	}