ARM: EXYNOS: Constify exynos_pm_data array

The 'exynos5420_pm_data' is not modified and can be made const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Pankaj Dubey <pankaj.dubey@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>

arch/arm/mach-exynos/suspend.c

@@ -576,7 +576,7 @@ static const struct exynos_pm_data exynos5250_pm_data = {
 	.cpu_suspend	= exynos_cpu_suspend,
 };
 
-static struct exynos_pm_data exynos5420_pm_data = {
+static const struct exynos_pm_data exynos5420_pm_data = {
 	.wkup_irq	= exynos5250_wkup_irq,
 	.wake_disable_mask = (0x7F << 7) | (0x1F << 1),
 	.release_ret_regs = exynos5420_release_ret_regs,