OMAPDSS: remove return from platform_driver_unreg

For unknown reasons we seem to have a return in each of the omapdss's
uninit functions, which is a void function.

Remove the returns.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/video/omap2/dss/dispc.c

@@ -3611,5 +3611,5 @@ int dispc_init_platform_driver(void)
 
 void dispc_uninit_platform_driver(void)
 {
-	return platform_driver_unregister(&omap_dispchw_driver);
+	platform_driver_unregister(&omap_dispchw_driver);
 }

drivers/video/omap2/dss/dsi.c

@@ -4814,5 +4814,5 @@ int dsi_init_platform_driver(void)
 
 void dsi_uninit_platform_driver(void)
 {
-	return platform_driver_unregister(&omap_dsihw_driver);
+	platform_driver_unregister(&omap_dsihw_driver);
 }

drivers/video/omap2/dss/dss.c

@@ -874,5 +874,5 @@ int dss_init_platform_driver(void)
 
 void dss_uninit_platform_driver(void)
 {
-	return platform_driver_unregister(&omap_dsshw_driver);
+	platform_driver_unregister(&omap_dsshw_driver);
 }

drivers/video/omap2/dss/hdmi.c

@@ -916,5 +916,5 @@ int hdmi_init_platform_driver(void)
 
 void hdmi_uninit_platform_driver(void)
 {
-	return platform_driver_unregister(&omapdss_hdmihw_driver);
+	platform_driver_unregister(&omapdss_hdmihw_driver);
 }

drivers/video/omap2/dss/rfbi.c

@@ -1039,5 +1039,5 @@ int rfbi_init_platform_driver(void)
 
 void rfbi_uninit_platform_driver(void)
 {
-	return platform_driver_unregister(&omap_rfbihw_driver);
+	platform_driver_unregister(&omap_rfbihw_driver);
 }

drivers/video/omap2/dss/venc.c

@@ -959,5 +959,5 @@ void venc_uninit_platform_driver(void)
 	if (cpu_is_omap44xx())
 		return;
 
-	return platform_driver_unregister(&omap_venchw_driver);
+	platform_driver_unregister(&omap_venchw_driver);
 }