Description: net: hso: do not call unregister if not registered
References:
 https://www.spinics.net/lists/linux-usb/msg202228.html
Notes:
 carnil> The original patch was not accepted:
 carnil> https://www.spinics.net/lists/linux-usb/msg202313.html
 carnil> and a fix probably never applied. Needs closer investigation.
Bugs:
upstream:
5.10-upstream-stable:
4.19-upstream-stable:
4.9-upstream-stable:
sid:
4.19-buster-security:
4.9-stretch-security: