use all variables containing hardening flags

Forwarded: https://github.com/amonakov/primus/pull/174
Last-Update: 2015-07-25

Gbp-Pq: Name hardening.patch

primus (0~20150328-12) unstable; urgency=medium

  * primus-nvidia: Build for arm64.

[dgit import unpatched primus 0~20150328-12]

Import primus_0~20150328-12.debian.tar.xz

[dgit import tarball primus 0~20150328-12 primus_0~20150328-12.debian.tar.xz]

Import primus_0~20150328.orig.tar.gz

[dgit import orig primus_0~20150328.orig.tar.gz]