drm/panel: s6e8aa0: Add dummy prepare and unprepare routines

This patch adds dummy definition for prepare and unprepare
routines to s6e8aa0 panel driver.

Signed-off-by: Ajay Kumar <ajaykumar.rs@samsung.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/panel/panel-s6e8aa0.c

@@ -903,6 +903,16 @@ static int s6e8aa0_disable(struct drm_panel *panel)
 	return s6e8aa0_power_off(ctx);
 }
 
+static int s6e8aa0_unprepare(struct drm_panel *panel)
+{
+	return 0;
+}
+
+static int s6e8aa0_prepare(struct drm_panel *panel)
+{
+	return 0;
+}
+
 static int s6e8aa0_enable(struct drm_panel *panel)
 {
 	struct s6e8aa0 *ctx = panel_to_s6e8aa0(panel);
@@ -947,6 +957,8 @@ static int s6e8aa0_get_modes(struct drm_panel *panel)
 
 static const struct drm_panel_funcs s6e8aa0_drm_funcs = {
 	.disable = s6e8aa0_disable,
+	.unprepare = s6e8aa0_unprepare,
+	.prepare = s6e8aa0_prepare,
 	.enable = s6e8aa0_enable,
 	.get_modes = s6e8aa0_get_modes,
 };