clk: samsung: exynos5433: mark PM functions as __maybe_unused

The suspend/resume functions are referenced conditionally, causing
a harmless warning when CONFIG_PM is disabled:

drivers/clk/samsung/clk-exynos5433.c:5476:12: error: 'exynos5433_cmu_resume' defined but not used [-Werror=unused-function]
drivers/clk/samsung/clk-exynos5433.c:5453:12: error: 'exynos5433_cmu_suspend' defined but not used [-Werror=unused-function]

This marks both as __maybe_unused to shut up the warning.

Fixes: 523d3de41f02 ("clk: samsung: exynos5433: Add support for runtime PM")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>

drivers/clk/samsung/clk-exynos5433.c

@@ -5450,7 +5450,7 @@ struct exynos5433_cmu_data {
 	struct samsung_clk_provider ctx;
 };
 
-static int exynos5433_cmu_suspend(struct device *dev)
+static int __maybe_unused exynos5433_cmu_suspend(struct device *dev)
 {
 	struct exynos5433_cmu_data *data = dev_get_drvdata(dev);
 	int i;
@@ -5473,7 +5473,7 @@ static int exynos5433_cmu_suspend(struct device *dev)
 	return 0;
 }
 
-static int exynos5433_cmu_resume(struct device *dev)
+static int __maybe_unused exynos5433_cmu_resume(struct device *dev)
 {
 	struct exynos5433_cmu_data *data = dev_get_drvdata(dev);
 	int i;