dmaengine: fsl_raid: make of_device_ids const.

of_device_ids are not supposed to change at runtime. All functions
working with of_device_ids provided by <linux/of.h> work with const
of_device_ids. So mark the non-const structs as const.

File size before:
text data bss dec hex filename
3981 608 0 4589 11ed drivers/dma/fsl_raid.o

File size after constify:
text data bss dec hex filename
4381 192 0 4573 11dd drivers/dma/fsl_raid.o

Signed-off-by: Arvind Yadav <[e-mail]>
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/fsl_raid.c

···
 	return 0;
 }
 
-static struct of_device_id fsl_re_ids[] = {
+static const struct of_device_id fsl_re_ids[] = {
 	{ .compatible = "fsl,raideng-v1.0", },
 	{}
 };