spi: tegra114: 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>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

drivers/spi/spi-tegra114.c

@@ -1012,7 +1012,7 @@ static irqreturn_t tegra_spi_isr(int irq, void *context_data)
 	return IRQ_WAKE_THREAD;
 }
 
-static struct of_device_id tegra_spi_of_match[] = {
+static const struct of_device_id tegra_spi_of_match[] = {
 	{ .compatible = "nvidia,tegra114-spi", },
 	{}
 };