fbdev: sh_mobile_lcdc: Return display connection state in display_on

Return true if the display is connected and false otherwise. Set the fb
info state to FBINFO_STATE_SUSPENDED in the sh_mobile_lcdc driver when
the display is not connected.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
diff --git a/drivers/video/sh_mobile_lcdcfb.h b/drivers/video/sh_mobile_lcdcfb.h
index b2cb8e6..6fb956c 100644
--- a/drivers/video/sh_mobile_lcdcfb.h
+++ b/drivers/video/sh_mobile_lcdcfb.h
@@ -21,6 +21,9 @@
 struct sh_mobile_lcdc_priv;
 struct sh_mobile_lcdc_chan;
 
+#define SH_MOBILE_LCDC_DISPLAY_DISCONNECTED	0
+#define SH_MOBILE_LCDC_DISPLAY_CONNECTED	1
+
 struct sh_mobile_lcdc_entity_ops {
 	/* Display */
 	int (*display_on)(struct sh_mobile_lcdc_entity *entity);