Drivers: hv: vmbus: Fix memory leak in vmbus_add_channel_kobj

kobject_init_and_add() takes reference even when it fails.
According to the doc of kobject_init_and_add()：

   If this function returns an error, kobject_put() must be called to
   properly clean up the memory associated with the object.

Fix memory leak by calling kobject_put().

Fixes: c2e5df6 ("vmbus: add per-channel sysfs info")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Juan Vazquez <juvazq@linux.microsoft.com>
Link: https://lore.kernel.org/r/20220203173008.43480-1-linmq006@gmail.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>

Author: Yuuoniy

drivers/hv/vmbus_drv.c

@@ -2028,8 +2028,10 @@ int vmbus_add_channel_kobj(struct hv_device *dev, struct vmbus_channel *channel)
 	kobj->kset = dev->channels_kset;
 	ret = kobject_init_and_add(kobj, &vmbus_chan_ktype, NULL,
 				   "%u", relid);
-	if (ret)
+	if (ret) {
+		kobject_put(kobj);
 		return ret;
+	}
 
 	ret = sysfs_create_group(kobj, &vmbus_chan_group);
 
@@ -2038,6 +2040,7 @@ int vmbus_add_channel_kobj(struct hv_device *dev, struct vmbus_channel *channel)
 		 * The calling functions' error handling paths will cleanup the
 		 * empty channel directory.
 		 */
+		kobject_put(kobj);
 		dev_err(device, "Unable to set up channel sysfs files\n");
 		return ret;
 	}