usb: phy: tegra: Make of_device_id array const

Make of_device_id array const, because all OF functions handle
it as const.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/phy/phy-tegra-usb.c b/drivers/usb/phy/phy-tegra-usb.c
index bbe4f8e..cd36cb4 100644
--- a/drivers/usb/phy/phy-tegra-usb.c
+++ b/drivers/usb/phy/phy-tegra-usb.c
@@ -965,7 +965,7 @@
 	.requires_extra_tuning_parameters = true,
 };
 
-static struct of_device_id tegra_usb_phy_id_table[] = {
+static const struct of_device_id tegra_usb_phy_id_table[] = {
 	{ .compatible = "nvidia,tegra30-usb-phy", .data = &tegra30_soc_config },
 	{ .compatible = "nvidia,tegra20-usb-phy", .data = &tegra20_soc_config },
 	{ },