Description: cx231xx-cards: fix NULL-deref on missing association descriptor
References:
 https://patchwork.kernel.org/patch/9963527/
Notes:
 bwh> Introduced in 2.6.30 by commit e0d3bafd0258 "V4L/DVB (10954): Add
 bwh> cx231xx USB driver"
Bugs:
upstream: released (4.15-rc1) [6c3b047fa2d2286d5e438bcb470c7b1a49f415f6]
4.9-upstream-stable: released (4.9.66) [38c043d26c97a04332df960200a389bc4141ff21]
3.16-upstream-stable: released (3.16.51) [99a3c1bb0ed332c64cfcd53a84fea2468ab9e11e]
3.2-upstream-stable: released (3.2.96) [59a7195cd497d430d9f76bc9f71cf53ed4102743]
sid: released (4.13.13-1) [bugfix/all/media-cx231xx-cards-fix-null-deref-on-missing-associ.patch]
4.9-stretch-security: released (4.9.65-1)
3.16-jessie-security: released (3.16.51-1)
3.2-wheezy-security: released (3.2.96-1)