iio: adc: ad_sigma_delta: change to buffer predisable

[ Upstream commit 66d4374d ]

Change the buffer disable callback from postdisable to predisable.
This balances the existing posteanble callback. Using postdisable
with posteanble can be problematic, for example, if update_scan_mode
fails, it would call postdisable without ever having called posteanble,
so the drivers using this would be in an unexpected state when
postdisable was called.

Fixes: af300848 ("iio:adc: Add common code for ADI Sigma Delta devices")
Signed-off-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://patch.msgid.link/20250703-iio-adc-ad_sigma_delta-buffer-predisable-v1-1-f2ab85138f1f@baylibre.com


Cc: <stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>