drm/msm/atomic: Clean up planes in the error paths of .atomic_commit()

When the .atomic_commit() handler fails, clean up planes previoulsy
prepared by drm_atomic_helper_prepare_planes() with a call to
drm_atomic_helper_cleanup_planes().

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Rob Clark <robdclark@gmail.com>
diff --git a/drivers/gpu/drm/msm/msm_atomic.c b/drivers/gpu/drm/msm/msm_atomic.c
index 84c0a72..b421c84 100644
--- a/drivers/gpu/drm/msm/msm_atomic.c
+++ b/drivers/gpu/drm/msm/msm_atomic.c
@@ -213,8 +213,10 @@
 		return ret;
 
 	c = commit_init(state);
-	if (!c)
-		return -ENOMEM;
+	if (!c) {
+		ret = -ENOMEM;
+		goto error;
+	}
 
 	/*
 	 * Figure out what crtcs we have:
@@ -247,7 +249,7 @@
 	ret = start_atomic(dev->dev_private, c->crtc_mask);
 	if (ret) {
 		kfree(c);
-		return ret;
+		goto error;
 	}
 
 	/*
@@ -291,4 +293,8 @@
 	complete_commit(c);
 
 	return 0;
+
+error:
+	drm_atomic_helper_cleanup_planes(dev, state);
+	return ret;
 }