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/nand/gpio.c b/drivers/mtd/nand/gpio.c
index 0cde618..2c2060b 100644
--- a/drivers/mtd/nand/gpio.c
+++ b/drivers/mtd/nand/gpio.c
@@ -316,8 +316,8 @@
 		gpiomtd->plat.adjust_parts(&gpiomtd->plat,
 					   gpiomtd->mtd_info.size);
 
-	add_mtd_partitions(&gpiomtd->mtd_info, gpiomtd->plat.parts,
-			   gpiomtd->plat.num_parts);
+	mtd_device_register(&gpiomtd->mtd_info, gpiomtd->plat.parts,
+			    gpiomtd->plat.num_parts);
 	platform_set_drvdata(dev, gpiomtd);
 
 	return 0;