drm: omapdrm: Simplify platform registration

Currently, calls into each file are used to register the various
platform drivers. Change this to a table of pointers to platform_driver
structs to allow using platform_register_drivers.

Signed-off-by: Andrew F. Davis <afd@ti.com>
diff --git a/drivers/gpu/drm/omapdrm/dss/venc.c b/drivers/gpu/drm/omapdrm/dss/venc.c
index b3e0e5f..6de9d73 100644
--- a/drivers/gpu/drm/omapdrm/dss/venc.c
+++ b/drivers/gpu/drm/omapdrm/dss/venc.c
@@ -984,7 +984,7 @@ static const struct of_device_id venc_of_match[] = {
 	{},
 };
 
-static struct platform_driver omap_venchw_driver = {
+struct platform_driver omap_venchw_driver = {
 	.probe		= venc_probe,
 	.remove		= venc_remove,
 	.driver         = {
@@ -994,13 +994,3 @@ static struct platform_driver omap_venchw_driver = {
 		.suppress_bind_attrs = true,
 	},
 };
-
-int __init venc_init_platform_driver(void)
-{
-	return platform_driver_register(&omap_venchw_driver);
-}
-
-void venc_uninit_platform_driver(void)
-{
-	platform_driver_unregister(&omap_venchw_driver);
-}