drm/tilcdc: tilcdc_tfp410: 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
   1496	    592	      0	   2088	    828	drivers/gpu/drm/tilcdc/tilcdc_tfp410.o

File size after constify:
   text	   data	    bss	    dec	    hex	filename
   1880	    176	      0	   2056	    808	drivers/gpu/drm/tilcdc/tilcdc_tfp410.o

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Jyri Sarha <jsarha@ti.com>

drivers/gpu/drm/tilcdc/tilcdc_tfp410.c

@@ -289,8 +289,6 @@ static const struct tilcdc_module_ops tfp410_module_ops = {
  * Device:
  */
 
-static struct of_device_id tfp410_of_match[];
-
 static int tfp410_probe(struct platform_device *pdev)
 {
 	struct device_node *node = pdev->dev.of_node;
@@ -375,7 +373,7 @@ static int tfp410_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static struct of_device_id tfp410_of_match[] = {
+static const struct of_device_id tfp410_of_match[] = {
 		{ .compatible = "ti,tilcdc,tfp410", },
 		{ },
 };