rtnl_link_af_unregister: fix locking
rtnl_link_af_unregister: fix locking

rtnl_link_af_unregister() attempts to write-lock info_lock twice
instead of releasing it before returning.  It also will return with
info_lock write-locked if passed a NULL ops.

Signed-off-by: Thomas Graf <17c2d8920621522552b392f72d8fdb4d1e866b44@suug.ch>

tgraf/libnl,dsahern/libnl,teto/libnl_old,tklauser/libnl,karlhiramoto/libnl,mshirley/libnl,vyos/libnl3,chitranshi/libnl,mshirley/libnl,mshirley/libnl,vyos/libnl3,chitranshi/libnl,UnicronNL/libnl3,cyclops8456/libnl3,honsys/libnl,chitranshi/libnl,houstar/libnl,baloo/libnl,greearb/libnl-ct,houstar/libnl,kolyshkin/libnl,dsahern/libnl,karlhiramoto/libnl,claudelee/libnl,claudelee/libnl,teto/libnl_old,teto/libnl_old,UnicronNL/libnl3,tgraf/libnl,Distrotech/libnl,cyclops8456/libnl3,mshirley/libnl,baloo/libnl,UnicronNL/libnl3,tgraf/libnl,claudelee/libnl,congwang/libnl,greearb/libnl-ct,Distrotech/libnl,kolyshkin/libnl,congwang/libnl,cyclops8456/libnl3,Distrotech/libnl,cyclops8456/libnl3,thom311/libnl,greearb/libnl-ct,vyos/libnl3,Distrotech/libnl,kolyshkin/libnl,baloo/libnl,HolyShitMan/libnl-1,claudelee/libnl,congwang/libnl,cfriedt/libnl,vyos/libnl3,karlhiramoto/libnl,tgraf/libnl,dsahern/libnl,baloo/libnl,honsys/libnl,chitranshi/libnl,kolyshkin/libnl,honsys/libnl,tklauser/libnl,HolyShitMan/libnl-1,houstar/libnl,honsys/libnl,tklauser/libnl,HolyShitMan/libnl-1,houstar/libnl,HolyShitMan/libnl-1,thom311/libnl,cfriedt/libnl,thom311/libnl,teto/libnl_old,tklauser/libnl,congwang/libnl,UnicronNL/libnl3,cfriedt/libnl,cfriedt/libnl,dsahern/libnl,karlhiramoto/libnl