OMAPDSS: split manager sysfs code

Separate sysfs code for managers to a separate file. This is a bit
cleaner, and will allow us later to easily switch off the sysfs support
via Kconfig option.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
diff --git a/drivers/video/omap2/dss/dss.h b/drivers/video/omap2/dss/dss.h
index 11b053e..5e9fd769 100644
--- a/drivers/video/omap2/dss/dss.h
+++ b/drivers/video/omap2/dss/dss.h
@@ -254,6 +254,10 @@
 		return false;
 }
 
+int dss_manager_kobj_init(struct omap_overlay_manager *mgr,
+		struct platform_device *pdev);
+void dss_manager_kobj_uninit(struct omap_overlay_manager *mgr);
+
 /* overlay */
 void dss_init_overlays(struct platform_device *pdev);
 void dss_uninit_overlays(struct platform_device *pdev);