drm/exynos: Suspend/resume is unused if !PM

Protect the suspend and resume callbacks with an #ifdef CONFIG_PM_SLEEP
guard to avoid "defined but not used" warnings.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.c b/drivers/gpu/drm/exynos/exynos_drm_drv.c
index 831d2e4..ae9e6b2 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_drv.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c
@@ -304,6 +304,7 @@
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
 static int exynos_drm_suspend(struct drm_device *dev, pm_message_t state)
 {
 	struct drm_connector *connector;
@@ -340,6 +341,7 @@
 
 	return 0;
 }
+#endif
 
 static int exynos_drm_open(struct drm_device *dev, struct drm_file *file)
 {