iio: dac: ti-dac082s085: 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: 61011264 ("iio: dac: Add Texas Instruments 8/10/12-bit 2/4-channel DAC driver")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20220508175712.647246-62-jic23@kernel.org

drivers/iio/dac/ti-dac082s085.c

@@ -55,7 +55,7 @@ struct ti_dac_chip {
 	bool powerdown;
 	u8 powerdown_mode;
 	u8 resolution;
-	u8 buf[2] ____cacheline_aligned;
+	u8 buf[2] __aligned(IIO_DMA_MINALIGN);
 };
 
 #define WRITE_NOT_UPDATE(chan)	(0x00 | (chan) << 6)