serial: avoid double free after call ioc4_serial_remove_one

  before goto out5,  soft, control, serial are all assigned to idd
  after finish call ioc4_serial_remove_one, all resources are released
  we need return instead of go on, or double free

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>