iio: adc: ad_sigma_delta: fix irq_flags on irq request

iio: adc: ad_sigma_delta: fix irq_flags on irq request

With commit 7b0c9f8fa3d2 ("iio: adc: ad_sigma_delta: Add optional irq
selection"), we can get the irq line from struct ad_sigma_delta_info
instead of the spi device. However, in devm_ad_sd_probe_trigger(), when
getting the irq_flags with irq_get_trigger_type() we are still using
the spi device irq instead of the one used for devm_request_irq().

Fixes: 7b0c9f8fa3d2 ("iio: adc: ad_sigma_delta: Add optional irq selection")
Signed-off-by: Nuno Sa <nuno.sa@analog.com>
Link: https://patch.msgid.link/20240806-dev-fix-ad-sigma-delta-v1-1-aa25b173c063@analog.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>