drm/panel: s6e8aa0: Add proper definition for prepare and unprepare

Move out code from enable and disable routines to prepare
and unprepare routines, so that functionality is properly
distributed across all the panel functions.
Signed-off-by: NAjay Kumar <ajaykumar.rs@samsung.com>
Signed-off-by: NThierry Reding <treding@nvidia.com>

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

@@ -891,6 +891,11 @@ static int s6e8aa0_power_off(struct s6e8aa0 *ctx)
 }
 
 static int s6e8aa0_disable(struct drm_panel *panel)
+{
+	return 0;
+}
+
+static int s6e8aa0_unprepare(struct drm_panel *panel)
 {
 	struct s6e8aa0 *ctx = panel_to_s6e8aa0(panel);
 
@@ -903,17 +908,7 @@ 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);
 	int ret;
@@ -926,11 +921,16 @@ static int s6e8aa0_enable(struct drm_panel *panel)
 	ret = ctx->error;
 
 	if (ret < 0)
-		s6e8aa0_disable(panel);
+		s6e8aa0_unprepare(panel);
 
 	return ret;
 }
 
+static int s6e8aa0_enable(struct drm_panel *panel)
+{
+	return 0;
+}
+
 static int s6e8aa0_get_modes(struct drm_panel *panel)
 {
 	struct drm_connector *connector = panel->connector;