usb: hso: remove the bailout parameter

There are two invocation sites of hso_free_net_device. After
refactoring hso_create_net_device, this parameter is useless.
Remove the bailout in the hso_free_net_device and change the invocation
sites of this function.

Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>