drm/panel: Constify OF match tables

Both the Samsung LD9040 and Samsung S6E8AA0 panel drivers are missing
a const qualifier for their OF match tables. This data is static and
never changes, so can be read-only.
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/panel/panel-ld9040.c

@@ -367,7 +367,7 @@ static int ld9040_remove(struct spi_device *spi)
 	return 0;
 }
 
-static struct of_device_id ld9040_of_match[] = {
+static const struct of_device_id ld9040_of_match[] = {
 	{ .compatible = "samsung,ld9040" },
 	{ }
 };

drivers/gpu/drm/panel/panel-s6e8aa0.c

@@ -1041,7 +1041,7 @@ static int s6e8aa0_remove(struct mipi_dsi_device *dsi)
 	return 0;
 }
 
-static struct of_device_id s6e8aa0_of_match[] = {
+static const struct of_device_id s6e8aa0_of_match[] = {
 	{ .compatible = "samsung,s6e8aa0" },
 	{ }
 };