mtd: Use mtd->name when registering nvmem device

With this patch, we use the mtd->name instead of concatenating the name
with '0'.

Fixes: c4dfa25a ("mtd: add support for reading MTD devices via the nvmem API")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>

drivers/mtd/mtdcore.c

@@ -507,6 +507,7 @@ static int mtd_nvmem_add(struct mtd_info *mtd)
 {
 	struct nvmem_config config = {};
 
+	config.id = -1;
 	config.dev = &mtd->dev;
 	config.name = mtd->name;
 	config.owner = THIS_MODULE;