mtd: docg3: fix a possible memory leak of mtd->name

In case DOC_CHIPID_G3, mtd->name is not freed in err handling path,
which is alloced by kasprintf(). Fix this by using devm_kasprintf().

Fixes: ae9d4934 ("mtd: docg3: add multiple floor support")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Boris Brezillon <bbrezillon@kernel.org>

drivers/mtd/devices/docg3.c

@@ -1767,8 +1767,8 @@ static int __init doc_set_driver_info(int chip_id, struct mtd_info *mtd)
 
 	switch (chip_id) {
 	case DOC_CHIPID_G3:
-		mtd->name = kasprintf(GFP_KERNEL, "docg3.%d",
-				      docg3->device_id);
+		mtd->name = devm_kasprintf(docg3->dev, GFP_KERNEL, "docg3.%d",
+					   docg3->device_id);
 		if (!mtd->name)
 			return -ENOMEM;
 		docg3->max_block = 2047;
@@ -1886,7 +1886,6 @@ static void doc_release_device(struct mtd_info *mtd)
 	mtd_device_unregister(mtd);
 	kfree(docg3->bbt);
 	kfree(docg3);
-	kfree(mtd->name);
 	kfree(mtd);
 }