mtd: virt-concat: free duplicate generated name

Every MTD registration runs mtd_virt_concat_create_join().  Once a
virtual concat has already been registered, the function builds the same
name again and takes the equal-name branch.  That branch skips to the
next item without freeing the newly allocated string.

Free the temporary name before continuing.

Fixes: 43db636 ("mtd: Add driver for concatenating devices")
Cc: stable@vger.kernel.org
Signed-off-by: Xu Rao <raoxu@uniontech.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Author: Xu Rao

drivers/mtd/mtd_virt_concat.c

@@ -321,8 +321,10 @@ int mtd_virt_concat_create_join(void)
 
 			if (concat->mtd.name) {
 				ret = memcmp(concat->mtd.name, name, name_sz);
-				if (ret == 0)
+				if (ret == 0) {
+					kfree(name);
 					continue;
+				}
 			}
 			mtd = mtd_concat_create(concat->subdev, concat->num_subdev, name);
 			if (!mtd) {