mtd: convert remaining users to mtd_device_register()

The older add_mtd_device()/add_mtd_partitions() and their removal
counterparts will soon be gone.  Replace uses with mtd_device_register()
and mtd_device_unregister().

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/maps/rpxlite.c b/drivers/mtd/maps/rpxlite.c
index 3e3ef53..ed88225 100644
--- a/drivers/mtd/maps/rpxlite.c
+++ b/drivers/mtd/maps/rpxlite.c
@@ -36,7 +36,7 @@
 	mymtd = do_map_probe("cfi_probe", &rpxlite_map);
 	if (mymtd) {
 		mymtd->owner = THIS_MODULE;
-		add_mtd_device(mymtd);
+		mtd_device_register(mymtd, NULL, 0);
 		return 0;
 	}
 
@@ -47,7 +47,7 @@
 static void __exit cleanup_rpxlite(void)
 {
 	if (mymtd) {
-		del_mtd_device(mymtd);
+		mtd_device_unregister(mymtd);
 		map_destroy(mymtd);
 	}
 	if (rpxlite_map.virt) {