DMA: shdma: make a pointer const

Platform data shouldn't be changed at run-time, so, pointers to it should
be const.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski+renesas@gmail.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/sh/shdma.c b/drivers/dma/sh/shdma.c
index e507bb28..3b4bee9 100644
--- a/drivers/dma/sh/shdma.c
+++ b/drivers/dma/sh/shdma.c
@@ -177,7 +177,7 @@
 static unsigned int calc_xmit_shift(struct sh_dmae_chan *sh_chan, u32 chcr)
 {
 	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
-	struct sh_dmae_pdata *pdata = shdev->pdata;
+	const struct sh_dmae_pdata *pdata = shdev->pdata;
 	int cnt = ((chcr & pdata->ts_low_mask) >> pdata->ts_low_shift) |
 		((chcr & pdata->ts_high_mask) >> pdata->ts_high_shift);
 
@@ -190,7 +190,7 @@
 static u32 log2size_to_chcr(struct sh_dmae_chan *sh_chan, int l2size)
 {
 	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
-	struct sh_dmae_pdata *pdata = shdev->pdata;
+	const struct sh_dmae_pdata *pdata = shdev->pdata;
 	int i;
 
 	for (i = 0; i < pdata->ts_shift_num; i++)
@@ -250,7 +250,7 @@
 static int dmae_set_dmars(struct sh_dmae_chan *sh_chan, u16 val)
 {
 	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
-	struct sh_dmae_pdata *pdata = shdev->pdata;
+	const struct sh_dmae_pdata *pdata = shdev->pdata;
 	const struct sh_dmae_channel *chan_pdata = &pdata->channel[sh_chan->shdma_chan.id];
 	void __iomem *addr = shdev->dmars;
 	unsigned int shift = chan_pdata->dmars_bit;
@@ -319,7 +319,7 @@
 	struct sh_dmae_chan *sh_chan, int match)
 {
 	struct sh_dmae_device *shdev = to_sh_dev(sh_chan);
-	struct sh_dmae_pdata *pdata = shdev->pdata;
+	const struct sh_dmae_pdata *pdata = shdev->pdata;
 	const struct sh_dmae_slave_config *cfg;
 	int i;
 
@@ -665,7 +665,7 @@
 
 static int sh_dmae_probe(struct platform_device *pdev)
 {
-	struct sh_dmae_pdata *pdata = pdev->dev.platform_data;
+	const struct sh_dmae_pdata *pdata = pdev->dev.platform_data;
 	unsigned long irqflags = IRQF_DISABLED,
 		chan_flag[SH_DMAE_MAX_CHANNELS] = {};
 	int errirq, chan_irq[SH_DMAE_MAX_CHANNELS];