OMAP: DSS2: move enable/disable_channel to overlay manager

Move enable/disable_channel() from omap_dss_device to overlay manager.

This is part of a larger patch-set, which moves the control from omapdss
driver to the display driver.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
diff --git a/drivers/video/omap2/dss/manager.c b/drivers/video/omap2/dss/manager.c
index 486cd4a..4ede519 100644
--- a/drivers/video/omap2/dss/manager.c
+++ b/drivers/video/omap2/dss/manager.c
@@ -1077,7 +1077,7 @@
 		mc->shadow_dirty = false;
 	}
 
-	dispc_enable_lcd_out(1);
+	dssdev->manager->enable(dssdev->manager);
 }
 
 static void dss_apply_irq_handler(void *data, u32 mask)
@@ -1364,6 +1364,18 @@
 	*info = mgr->info;
 }
 
+static int dss_mgr_enable(struct omap_overlay_manager *mgr)
+{
+	dispc_enable_channel(mgr->id, 1);
+	return 0;
+}
+
+static int dss_mgr_disable(struct omap_overlay_manager *mgr)
+{
+	dispc_enable_channel(mgr->id, 0);
+	return 0;
+}
+
 static void omap_dss_add_overlay_manager(struct omap_overlay_manager *manager)
 {
 	++num_managers;
@@ -1409,6 +1421,9 @@
 		mgr->wait_for_go = &dss_mgr_wait_for_go;
 		mgr->wait_for_vsync = &dss_mgr_wait_for_vsync;
 
+		mgr->enable = &dss_mgr_enable;
+		mgr->disable = &dss_mgr_disable;
+
 		mgr->caps = OMAP_DSS_OVL_MGR_CAP_DISPC;
 
 		dss_overlay_setup_dispc_manager(mgr);