[PATCH] iio: proximity: pulsedlight: fix iio_device left registered on PM setup failure

pm_runtime_set_active() failing in probe() jumps to error_unreg_buffer,
which only calls iio_triggered_buffer_cleanup() -- it does not undo the
iio_device_register() that already succeeded a few lines above. probe()
then returns the error, the devm-managed indio_dev is freed, but the
iio core still has it registered: the sysfs/chardev nodes stay live and
point at freed memory.

Add an error_unreg_dev label that unregisters the iio device before
falling through to the existing buffer cleanup, mirroring the teardown
order already used in lidar_remove().

Fixes: 4ac4e086fd8c ("iio: pulsedlight-lidar-lite: add runtime PM")
Assisted-by: Claude:claude-opus-4
Signed-off-by: Cong Nguyen <[email protected]>
---
 drivers/iio/proximity/pulsedlight-lidar-lite-v2.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c b/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c
index 400477b4c740..8a9ee21f2bf6 100644
--- a/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c
+++ b/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c
@@ -294,12 +294,14 @@ static int lidar_probe(struct i2c_client *client)
 
 	ret = pm_runtime_set_active(&client->dev);
 	if (ret)
-		goto error_unreg_buffer;
+		goto error_unreg_dev;
 	pm_runtime_enable(&client->dev);
 	pm_runtime_idle(&client->dev);
 
 	return 0;
 
+error_unreg_dev:
+	iio_device_unregister(indio_dev);
 error_unreg_buffer:
 	iio_triggered_buffer_cleanup(indio_dev);
 
-- 
2.25.1