iio: adc: ad7292: Fix alignment for DMA safety

____cacheline_aligned is an insufficient guarantee for non-coherent DMA
on platforms with 128 byte cachelines above L1. Switch to the updated
IIO_DMA_MINALIGN definition.

Fixes: 506d2e317a0a ("iio: adc: Add driver support for AD7292")
Signed-off-by: Jonathan Cameron <[e-mail]>
Acked-by: Marcelo Schmitt <[e-mail]>
Acked-by: Nuno Sá <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/iio/adc/ad7292.c

···
 	struct regulator *reg;
 	unsigned short vref_mv;
 
-	__be16 d16 ____cacheline_aligned;
+	__be16 d16 __aligned(IIO_DMA_MINALIGN);
 	u8 d8[2];
 };