spi: dw-mid: constify dw_spi_dma_ops structure

The dw_spi_dma_ops structure is never modified, so declare it as const.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h
index 35589a2..61bc3cb 100644
--- a/drivers/spi/spi-dw.h
+++ b/drivers/spi/spi-dw.h
@@ -130,7 +130,7 @@
 	struct dma_chan		*rxchan;
 	unsigned long		dma_chan_busy;
 	dma_addr_t		dma_addr; /* phy address of the Data register */
-	struct dw_spi_dma_ops	*dma_ops;
+	const struct dw_spi_dma_ops *dma_ops;
 	void			*dma_tx;
 	void			*dma_rx;