OMAPDSS: fix DPI and SDI device ids

The DPI and SDI platform devices are currently created with the ID of
-1. The ID doesn't currently affect anything.

However, we have added regulator supply entries for "omapdss_dpi.0" and
"omapdss_sdi.0" to the board files, although these supply entries are
not yet used. As the ID used for the devices is -1, these regulator
supply entries will not work.

To fix the issue, assign ID of 0 to the devices. In the future there may
be more than one DPI or SDI output, so it makes sense to have a proper
ID for them.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Archit Taneja <archit@ti.com>
diff --git a/arch/arm/mach-omap2/display.c b/arch/arm/mach-omap2/display.c
index ff37be1..03a0516 100644
--- a/arch/arm/mach-omap2/display.c
+++ b/arch/arm/mach-omap2/display.c
@@ -400,7 +400,7 @@
 
 	/* Create devices for DPI and SDI */
 
-	pdev = create_simple_dss_pdev("omapdss_dpi", -1,
+	pdev = create_simple_dss_pdev("omapdss_dpi", 0,
 			board_data, sizeof(*board_data), dss_pdev);
 	if (IS_ERR(pdev)) {
 		pr_err("Could not build platform_device for omapdss_dpi\n");
@@ -408,7 +408,7 @@
 	}
 
 	if (cpu_is_omap34xx()) {
-		pdev = create_simple_dss_pdev("omapdss_sdi", -1,
+		pdev = create_simple_dss_pdev("omapdss_sdi", 0,
 				board_data, sizeof(*board_data), dss_pdev);
 		if (IS_ERR(pdev)) {
 			pr_err("Could not build platform_device for omapdss_sdi\n");