OMAPDSS: disable VT switch

We don't need VT switch when suspending/resuming, so disable it. This
speeds up suspend/resume.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: NeilBrown <neil@brown.name>
diff --git a/drivers/video/fbdev/omap2/dss/dss.c b/drivers/video/fbdev/omap2/dss/dss.c
index a6d10d4..7f978b6 100644
--- a/drivers/video/fbdev/omap2/dss/dss.c
+++ b/drivers/video/fbdev/omap2/dss/dss.c
@@ -38,6 +38,7 @@
 #include <linux/regmap.h>
 #include <linux/of.h>
 #include <linux/regulator/consumer.h>
+#include <linux/suspend.h>
 
 #include <video/omapdss.h>
 
@@ -1138,6 +1139,8 @@
 
 	dss_debugfs_create_file("dss", dss_dump_regs);
 
+	pm_set_vt_switch(0);
+
 	return 0;
 
 err_pll_init: