omapfb: Create new header file for omapfb DSS implementation

Copy the content of video/omapdss.h to a new (video/omapfb_dss.h) header
file and convert the omapfb drivers to use this new file.

The new header file is needed to complete the separation of omapdrm and
omapfb implementation of DSS.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
diff --git a/drivers/video/fbdev/omap2/omapfb/displays/panel-dsi-cm.c b/drivers/video/fbdev/omap2/omapfb/displays/panel-dsi-cm.c
index a4eac69..b58012b 100644
--- a/drivers/video/fbdev/omap2/omapfb/displays/panel-dsi-cm.c
+++ b/drivers/video/fbdev/omap2/omapfb/displays/panel-dsi-cm.c
@@ -25,7 +25,7 @@
 #include <linux/of_device.h>
 #include <linux/of_gpio.h>
 
-#include <video/omapdss.h>
+#include <video/omapfb_dss.h>
 #include <video/mipi_display.h>
 
 /* DSI Virtual channel. Hardcoded for now. */