iio: adc: ad_sigma_delta: change to buffer predisable

commit 66d4374d upstream.

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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>