gpio: tegra: Make of_device_id compatible data to constant

The data member of the of_device_id is the constant type
and hence all static structure which is used for this
initialisation as static.
Signed-off-by: NLaxman Dewangan <ldewangan@nvidia.com>
Suggested-by: NThierry Reding <treding@nvidia.com>
Reviewed-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-tegra.c

@@ -560,12 +560,12 @@ static int tegra_gpio_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static struct tegra_gpio_soc_config tegra20_gpio_config = {
+static const struct tegra_gpio_soc_config tegra20_gpio_config = {
 	.bank_stride = 0x80,
 	.upper_offset = 0x800,
 };
 
-static struct tegra_gpio_soc_config tegra30_gpio_config = {
+static const struct tegra_gpio_soc_config tegra30_gpio_config = {
 	.bank_stride = 0x100,
 	.upper_offset = 0x80,
 };