nand: Don't use qdev_create() in nand_init()

Commit 7426aa72 (nand: Don't inherit
from Sysbus) changed the parent type of TYPE_NAND but continued to use
qdev_create(), which handled a NULL BusState as SysBus.

Use object_new() instead, and reuse the TYPE_NAND define while at it.
Reported-by: NMarkus Armbruster <armbru@redhat.com>
Cc: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: NIgor Mammedov <imammedo@redhat.com>
Signed-off-by: NAndreas Färber <afaerber@suse.de>

hw/block/nand.c

@@ -632,7 +632,7 @@ DeviceState *nand_init(BlockDriverState *bdrv, int manf_id, int chip_id)
     if (nand_flash_ids[chip_id].size == 0) {
         hw_error("%s: Unsupported NAND chip ID.\n", __FUNCTION__);
     }
-    dev = qdev_create(NULL, "nand");
+    dev = DEVICE(object_new(TYPE_NAND));
     qdev_prop_set_uint8(dev, "manufacturer_id", manf_id);
     qdev_prop_set_uint8(dev, "chip_id", chip_id);
     if (bdrv) {