Drivers: hv: vmbus: Fix memory leak in vmbus_add_channel_kobj

In the Linux kernel, the following vulnerability has been resolved:

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().